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>
diff --git a/lib/string.c b/lib/string.c
index a1cdcfcc..0f86245 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -36,25 +36,21 @@
 	/* Yes, Virginia, it had better be unsigned */
 	unsigned char c1, c2;
 
-	c1 = c2 = 0;
-	if (len) {
-		do {
-			c1 = *s1;
-			c2 = *s2;
-			s1++;
-			s2++;
-			if (!c1)
-				break;
-			if (!c2)
-				break;
-			if (c1 == c2)
-				continue;
-			c1 = tolower(c1);
-			c2 = tolower(c2);
-			if (c1 != c2)
-				break;
-		} while (--len);
-	}
+	if (!len)
+		return 0;
+
+	do {
+		c1 = *s1++;
+		c2 = *s2++;
+		if (!c1 || !c2)
+			break;
+		if (c1 == c2)
+			continue;
+		c1 = tolower(c1);
+		c2 = tolower(c2);
+		if (c1 != c2)
+			break;
+	} while (--len);
 	return (int)c1 - (int)c2;
 }
 EXPORT_SYMBOL(strnicmp);