[build-script] When building packages install llvm-cov, llvm-profdata for use with swiftpm.

rdar://44567818

Author: gottesmm

utils/build-presets.ini

@@ -726,6 +726,7 @@ install-swiftpm
 install-xctest
 install-prefix=/usr
 swift-install-components=autolink-driver;compiler;clang-builtin-headers;stdlib;swift-remote-mirror;sdk-overlay;license;sourcekit-inproc
+llvm-install-components=llvm-cov;llvm-profdata
 build-swift-static-stdlib
 build-swift-static-sdk-overlay
 build-swift-stdlib-unittest-extra
@@ -1025,6 +1026,7 @@ test-installable-package
 reconfigure
 
 swift-install-components=compiler;clang-builtin-headers;stdlib;swift-syntax;sdk-overlay;license;sourcekit-xpc-service;swift-remote-mirror;swift-remote-mirror-headers
+llvm-install-components=llvm-cov;llvm-profdata
 
 # Path to the .tar.gz package we would create.
 installable-package=%(installable_package)s