common/rc: fix _get_max_lfs_filesize on 32-bit platforms

The 32-bit calculation of the maximum filesize is incorrect.  Replace it
with the formula that the kernel has used since commit 0cc3b0ec23ce
("Clarify (and fix) MAX_LFS_FILESIZE macros").  This fixes a regression
in generic/351 on 32-bit kernels.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
diff --git a/common/rc b/common/rc
index eeac135..cf6bc9d 100644
--- a/common/rc
+++ b/common/rc
@@ -3999,7 +3999,9 @@
 {
 	case "$(getconf LONG_BIT)" in
 	"32")
-		echo $(( ($(getconf PAGE_SIZE) << ($(getconf LONG_BIT) - 1) ) - 1))
+		local ulong_max=$(getconf ULONG_MAX)
+		local page_size=$(getconf PAGE_SIZE)
+		echo $(( ulong_max * page_size ))
 		;;
 	"64")
 		echo 9223372036854775807