libbb: add is_suffixed_with() function

Signed-off-by: Bartosz Golaszewski <bartekgola@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/include/libbb.h b/include/libbb.h
index 2e20706..543214e 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -413,6 +413,7 @@
 char *last_char_is(const char *s, int c) FAST_FUNC;
 const char* endofname(const char *name) FAST_FUNC;
 char *is_prefixed_with(const char *string, const char *key) FAST_FUNC;
+char *is_suffixed_with(const char *string, const char *key) FAST_FUNC;
 
 int ndelay_on(int fd) FAST_FUNC;
 int ndelay_off(int fd) FAST_FUNC;