erofs-utils: build: cure compiler warnings

On i586 I observe:

In file included from inode.c:16:
inode.c: In function 'erofs_mkfs_build_tree':
../include/erofs/print.h:27:21: error: format '%lu' expects argument of type
'long unsigned int', but argument 7 has type 'erofs_nid_t' {aka 'long long unsigned int'} [-Werror=format=]
   27 | #define pr_fmt(fmt) "EROFS: " FUNC_LINE_FMT fmt "\n"
../include/erofs/print.h:43:4: note: in expansion of macro 'pr_fmt'
   43 |    pr_fmt(fmt),    \
inode.c:792:3: note: in expansion of macro 'erofs_info'
  792 |   erofs_info("add file %s/%s (nid %lu, type %d)",
inode.c:792:37: note: format string is defined here
  792 |   erofs_info("add file %s/%s (nid %lu, type %d)",

Signed-off-by: Jan Engelhardt <jengelh@inai.de>
[ Gao Xiang: minor update, and fix subject line. ]
Signed-off-by: Gao Xiang <hsiangkao@aol.com>
2 files changed