fstests: fix blksize_t printf format warnings across architectures

fstests: fix blksize_t printf format warnings across architectures

Fix format string warnings when printing blksize_t values that vary
across architectures. The warning occurs because blksize_t is defined
differently between architectures: aarch64 architectures blksize_t is
int, on x86-64 it's long-int.  Cast the values to long. Fixes warnings
as below.

 seek_sanity_test.c:110:45: warning: format '%ld' expects argument of type
 'long int', but argument 3 has type 'blksize_t' {aka 'int'}

 attr_replace_test.c:70:22: warning: format '%ld' expects argument of type
 'long int', but argument 3 has type '__blksize_t' {aka 'int'}

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Zorro Lang <zlang@kernel.org>