[llvm][Support] Fix backtrace output by removing '#'. NFC

- '#' has the string "0x" prepended for non-zero values. That results in
  inconsistent behavior between zero and non-zero values.

Author: darkbuck

llvm/lib/Support/Unix/Signals.inc

@@ -539,7 +539,7 @@ public:
       uintptr_t StartAddress = Info->dlpi_addr + Phdr->p_vaddr;
       uintptr_t ModuleRelativeAddress = Phdr->p_vaddr;
       std::array<char, 4> ModeStr = modeStrFromFlags(Phdr->p_flags);
-      OS << format("{{{mmap:%#016x:%#x:load:%d:%s:%#016x}}}\n", StartAddress,
+      OS << format("{{{mmap:%016x:%x:load:%d:%s:%016x}}}\n", StartAddress,
                    Phdr->p_memsz, ModuleCount, &ModeStr[0],
                    ModuleRelativeAddress);
     }

llvm/unittests/Support/SignalsTest.cpp

@@ -46,7 +46,7 @@ TEST(SignalsTest, PrintsSymbolizerMarkup) {
   EXPECT_THAT(
       Res,
       MatchesRegex(".*" TAG_BEGIN
-                   "mmap:0x[0-9a-f]+:0x[0-9a-f]+:load:0:rx:[0-9a-f]+" TAG_END
+                   "mmap:[0-9a-f]+:[0-9a-f]+:load:0:rx:[0-9a-f]+" TAG_END
                    ".*"));
   // Backtrace line
   EXPECT_THAT(Res, MatchesRegex(".*" TAG_BEGIN "bt:0:[0-9a-f]+"