staging: erofs: fix a compile warning of Z_EROFS_VLE_VMAP_ONSTACK_PAGES

There is a type mismatch in the definition of
Z_EROFS_VLE_VMAP_ONSTACK_PAGES, let's fix it.

Link: https://lists.01.org/pipermail/kbuild-all/2018-July/050707.html
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/erofs/unzip_vle.h

@@ -218,7 +218,7 @@ static inline void z_erofs_onlinepage_endio(struct page *page)
 }
 
 #define Z_EROFS_VLE_VMAP_ONSTACK_PAGES	\
-	min(THREAD_SIZE / 8 / sizeof(struct page *), 96UL)
+	min_t(unsigned int, THREAD_SIZE / 8 / sizeof(struct page *), 96U)
 #define Z_EROFS_VLE_VMAP_GLOBAL_PAGES	2048
 
 /* unzip_vle_lz4.c */