lstat_cache(): introduce clear_lstat_cache() function

If you want to completely clear the contents of the lstat_cache(), then
call this new function.

Signed-off-by: Kjetil Barvik <barvik@broadpark.no>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

cache.h

@@ -723,6 +723,7 @@ extern int has_symlink_leading_path(int len, const char *name);
 extern int has_symlink_or_noent_leading_path(int len, const char *name);
 extern int has_dirs_only_path(int len, const char *name, int prefix_len);
 extern void invalidate_lstat_cache(int len, const char *name);
+extern void clear_lstat_cache(void);
 
 extern struct alternate_object_database {
 	struct alternate_object_database *next;

symlinks.c

@@ -195,6 +195,14 @@ void invalidate_lstat_cache(int len, const char *name)
 	}
 }
 
+/*
+ * Completely clear the contents of the cache
+ */
+void clear_lstat_cache(void)
+{
+	reset_lstat_cache(0, 0);
+}
+
 #define USE_ONLY_LSTAT  0
 
 /*