[sanitizer_common][test] Fix huge_malloc.c UNSUPPORTED syntax

[ro]

Summary

lit doesn't accept arbitrary substrings of the target triple any longer, so d5a779b5a39b655ed9fafedaacbb017c46f5dbfe has no effect.

Instead, this patch uses the target= syntax as all other tests in compiler-rt.

Tested on amd64-pc-solaris2.11.

Will commit shortly to unbreak the Solaris/amd64 buildbot.

compiler-rt/test/sanitizer_common/TestCases/Posix/huge_malloc.c

 // RUN: %clang -O0 %s -o %t && %env_tool_opts=allocator_may_return_null=1:hard_rss_limit_mb=50:quarantine_size_mb=1 %run %t
 
 #include <stdlib.h>
 #include <stdio.h>
 
 // https://github.com/google/sanitizers/issues/981
 // UNSUPPORTED: android-26
 
 // FIXME: Hangs.
 // UNSUPPORTED: tsan
 
 // Hwasan requires tagging of new allocations, so needs RSS for shadow.
 // UNSUPPORTED: hwasan
 
 // FIXME: Something wrong with MADV_FREE or MAP_NORESERVE there.
-// UNSUPPORTED: solaris
+// UNSUPPORTED: target={{.*solaris.*}}
 
 void *p;
 
 int main(int argc, char **argv) {
   for (int i = 0; i < sizeof(void *) * 8; ++i) {
     // Calloc avoids MSAN shadow poisoning.
     p = calloc(1ull << i, 1);
     fprintf(stderr, "%d %llu: %p\n", i, (1ull << i), p);
     free(p);
   }
   return 0;
 }