chrreplace: Don't skip the first character

Check if the first character matches the character to replace, rather
than skipping it and starting with the second.

Signed-off-by: Josh Triplett <josh@joshtriplett.org>

com32/lib/chrreplace.c

@@ -4,8 +4,8 @@
 void chrreplace(char *source, char old, char new) 
 {
     while (*source) { 
-	source++;
 	if (source[0] == old) source[0]=new;
+	source++;
     }
 }