[libc++][test] extend -linux-gnu XFAIL to cover all of the -linux targets (#129140)

The default triple of Amazon Linux on AArch64 is aarch64-amazon-linux,
see issue highlighded by PR #109263, somewhat serious linker issues are
encountered if any other triple is being used.

Unfortunately, this makes XFAIL lines like:
`XFAIL: target=aarch64{{.*}}-linux-gnu` ineffective,
making it impossible to complete all of the check-cxx without failures.

Author: pawosm-arm

libcxx/test/std/input.output/iostream.format/std.manip/setfill_wchar_max.pass.cpp

@@ -16,7 +16,7 @@
 
 // XFAIL: target={{.*}}-windows{{.*}} && libcpp-abi-version=1
 // XFAIL: target=armv{{7|8}}{{l?}}{{.*}}-linux-gnueabihf && libcpp-abi-version=1
-// XFAIL: target=aarch64{{.*}}-linux-gnu && libcpp-abi-version=1
+// XFAIL: target=aarch64{{.*}}-linux{{.*}} && libcpp-abi-version=1
 
 #include <iomanip>
 #include <ostream>

libcxx/test/std/re/re.alg/re.alg.match/awk.locale.pass.cpp

@@ -18,7 +18,7 @@
 
 // TODO: investigation needed
 // TODO(netbsd): incomplete support for locales
-// XFAIL: target={{.*}}-linux-gnu{{.*}}, netbsd, freebsd
+// XFAIL: target={{.*}}-linux{{.*}}, netbsd, freebsd
 // REQUIRES: locale.cs_CZ.ISO8859-2
 
 #include <regex>

libcxx/test/std/re/re.alg/re.alg.match/basic.locale.pass.cpp

@@ -22,7 +22,7 @@
 //                  regex_constants::match_flag_type flags = regex_constants::match_default);
 
 // TODO: investigation needed
-// XFAIL: target={{.*}}-linux-gnu{{.*}}, freebsd
+// XFAIL: target={{.*}}-linux{{.*}}, freebsd
 
 #include <regex>
 #include <cassert>

libcxx/test/std/re/re.alg/re.alg.match/ecma.locale.pass.cpp

@@ -22,7 +22,7 @@
 //                  regex_constants::match_flag_type flags = regex_constants::match_default);
 
 // TODO: investigation needed
-// XFAIL: target={{.*}}-linux-gnu{{.*}}, freebsd
+// XFAIL: target={{.*}}-linux{{.*}}, freebsd
 
 #include <regex>
 #include <cassert>

libcxx/test/std/re/re.alg/re.alg.match/extended.locale.pass.cpp

@@ -22,7 +22,7 @@
 //                  regex_constants::match_flag_type flags = regex_constants::match_default);
 
 // TODO: investigation needed
-// XFAIL: target={{.*}}-linux-gnu{{.*}}, freebsd
+// XFAIL: target={{.*}}-linux{{.*}}, freebsd
 
 #include <regex>
 #include <cassert>

libcxx/test/std/re/re.alg/re.alg.search/awk.locale.pass.cpp

@@ -22,7 +22,7 @@
 //                  regex_constants::match_flag_type flags = regex_constants::match_default);
 
 // TODO: investigation needed
-// XFAIL: target={{.*}}-linux-gnu{{.*}}, freebsd
+// XFAIL: target={{.*}}-linux{{.*}}, freebsd
 
 #include <regex>
 #include <cassert>

libcxx/test/std/re/re.alg/re.alg.search/basic.locale.pass.cpp

@@ -22,7 +22,7 @@
 //                  regex_constants::match_flag_type flags = regex_constants::match_default);
 
 // TODO: investigation needed
-// XFAIL: target={{.*}}-linux-gnu{{.*}}, freebsd
+// XFAIL: target={{.*}}-linux{{.*}}, freebsd
 
 #include <regex>
 #include <cassert>

libcxx/test/std/re/re.alg/re.alg.search/ecma.locale.pass.cpp

@@ -22,7 +22,7 @@
 //                  regex_constants::match_flag_type flags = regex_constants::match_default);
 
 // TODO: investigation needed
-// XFAIL: target={{.*}}-linux-gnu{{.*}}, freebsd
+// XFAIL: target={{.*}}-linux{{.*}}, freebsd
 
 #include <regex>
 #include <cassert>

libcxx/test/std/re/re.alg/re.alg.search/extended.locale.pass.cpp

@@ -22,7 +22,7 @@
 //                  regex_constants::match_flag_type flags = regex_constants::match_default);
 
 // TODO: investigation needed
-// XFAIL: target={{.*}}-linux-gnu{{.*}}, freebsd
+// XFAIL: target={{.*}}-linux{{.*}}, freebsd
 
 #include <regex>
 #include <cassert>

libcxx/test/std/re/re.traits/lookup_collatename.pass.cpp

@@ -23,7 +23,7 @@
 //   lookup_collatename(ForwardIterator first, ForwardIterator last) const;
 
 // TODO: investigation needed
-// XFAIL: target={{.*}}-linux-gnu{{.*}}
+// XFAIL: target={{.*}}-linux{{.*}}
 
 #include <regex>
 #include <iterator>