[PATCH] selftests/powerpc: use MAP_FAILED instead of (void *)-1 in tm-signal-context-force-tm

mmap() is documented to return MAP_FAILED on error, but
tm-signal-context-force-tm.c compares the return value against
(void *)-1. Replace these with the standard MAP_FAILED macro for
better readability and type safety.

Signed-off-by: longlong yan <[email protected]>
---
 .../testing/selftests/powerpc/tm/tm-signal-context-force-tm.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/powerpc/tm/tm-signal-context-force-tm.c b/tools/testing/selftests/powerpc/tm/tm-signal-context-force-tm.c
index 0a4bc479ae39..5dc0f12f467d 100644
--- a/tools/testing/selftests/powerpc/tm/tm-signal-context-force-tm.c
+++ b/tools/testing/selftests/powerpc/tm/tm-signal-context-force-tm.c
@@ -60,7 +60,7 @@ void usr_signal_handler(int signo, siginfo_t *si, void *uc)
 	ucp->uc_link = mmap(NULL, sizeof(ucontext_t),
 			    PROT_READ | PROT_WRITE,
 			    MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
-	if (ucp->uc_link == (void *)-1) {
+	if (ucp->uc_link == MAP_FAILED) {
 		perror("Mmap failed");
 		exit(-1);
 	}
@@ -129,7 +129,7 @@ void tm_trap_test(void)
 		ss.ss_size = SIGSTKSZ;
 		ss.ss_flags = 0;
 
-		if (ss.ss_sp == (void *)-1) {
+		if (ss.ss_sp == MAP_FAILED) {
 			perror("mmap error\n");
 			exit(-1);
 		}
-- 
2.43.0