Use -Zno-profiler-runtime instead of //@ needs-profiler-support

For PGO/coverage tests that don't need to build or run an actual artifact, we
can use `-Zno-profiler-runtime` to run the test even when the profiler runtime
is not available.

tests/ui/instrument-coverage/coverage-options.rs

@@ -1,6 +1,5 @@
-//@ needs-profiler-support
 //@ revisions: block branch condition mcdc bad
-//@ compile-flags -Cinstrument-coverage
+//@ compile-flags -Cinstrument-coverage -Zno-profiler-runtime
 
 //@ [block] check-pass
 //@ [block] compile-flags: -Zcoverage-options=block

tests/ui/instrument-coverage/on-values.rs

@@ -1,5 +1,5 @@
 //@ check-pass
-//@ needs-profiler-support
+//@ compile-flags: -Zno-profiler-runtime
 //@ revisions: default y yes on true_ all
 //@ [default] compile-flags: -Cinstrument-coverage
 //@ [y] compile-flags: -Cinstrument-coverage=y