proc: return exit code 4 for skipped tests

Test harness uses 4 for SKIP, not 2.

Link: http://lkml.kernel.org/r/20190108193108.GA12259@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

tools/testing/selftests/proc/proc-loadavg-001.c

@@ -30,7 +30,7 @@ int main(void)
 
 	if (unshare(CLONE_NEWPID) == -1) {
 		if (errno == ENOSYS || errno == EPERM)
-			return 2;
+			return 4;
 		return 1;
 	}
 

tools/testing/selftests/proc/proc-self-map-files-002.c

@@ -63,7 +63,7 @@ int main(void)
 	p = mmap((void *)va, PAGE_SIZE, PROT_NONE, MAP_PRIVATE|MAP_FILE|MAP_FIXED, fd, 0);
 	if (p == MAP_FAILED) {
 		if (errno == EPERM)
-			return 2;
+			return 4;
 		return 1;
 	}
 

tools/testing/selftests/proc/proc-self-syscall.c

@@ -39,7 +39,7 @@ int main(void)
 	fd = open("/proc/self/syscall", O_RDONLY);
 	if (fd == -1) {
 		if (errno == ENOENT)
-			return 2;
+			return 4;
 		return 1;
 	}
 

tools/testing/selftests/proc/proc-self-wchan.c

@@ -27,7 +27,7 @@ int main(void)
 	fd = open("/proc/self/wchan", O_RDONLY);
 	if (fd == -1) {
 		if (errno == ENOENT)
-			return 2;
+			return 4;
 		return 1;
 	}
 

tools/testing/selftests/proc/read.c

@@ -126,7 +126,7 @@ int main(void)
 
 	d = opendir("/proc");
 	if (!d)
-		return 2;
+		return 4;
 	f(d, 0);
 	return 0;
 }