lib/string.c: simplify stricmp()

Removes 32 bytes on core2 with gcc 4.4.1:
   text    data     bss     dec     hex filename
   3196       0       0    3196     c7c lib/string-BEFORE.o
   3164       0       0    3164     c5c lib/string-AFTER.o
Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/string.c

@@ -36,16 +36,13 @@ int strnicmp(const char *s1, const char *s2, size_t len)
 	/* Yes, Virginia, it had better be unsigned */
 	unsigned char c1, c2;
 
-	c1 = c2 = 0;
-	if (len) {
+	if (!len)
+		return 0;
+
 	do {
-			c1 = *s1;
-			c2 = *s2;
-			s1++;
-			s2++;
-			if (!c1)
-				break;
-			if (!c2)
+		c1 = *s1++;
+		c2 = *s2++;
+		if (!c1 || !c2)
 			break;
 		if (c1 == c2)
 			continue;
@@ -54,7 +51,6 @@ int strnicmp(const char *s1, const char *s2, size_t len)
 		if (c1 != c2)
 			break;
 	} while (--len);
-	}
 	return (int)c1 - (int)c2;
 }
 EXPORT_SYMBOL(strnicmp);