improve readability of string: fix indentation and remove trailing spaces

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
diff --git a/libc/string/strncmp.c b/libc/string/strncmp.c
index 9da41ab..1768808 100644
--- a/libc/string/strncmp.c
+++ b/libc/string/strncmp.c
@@ -38,14 +38,13 @@
 int
 strncmp(const char *s1, const char *s2, size_t n)
 {
-
 	if (n == 0)
 		return (0);
 	do {
 		if (*s1 != *s2++)
 			return (*(unsigned char *)s1 - *(unsigned char *)--s2);
 		if (*s1++ == 0)
-      break;
+			break;
 	} while (--n != 0);
 	return (0);
 }