LU-16518 mdt: implicit truncation to a one-bit field

LU-16518 mdt: implicit truncation to a one-bit field

Change the uc_rbac one-bit fields to unsigned int
to avoid an implicit truncation error reported by
Clang (-Wsingle-bit-bitfield-constant-conversion).

Test-Parameters: trivial
Signed-off-by: Timothy Day <timday@amazon.com>
Change-Id: I394e71d5d572d4586de55093d4cc60729041a822
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/58347
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Sebastien Buisson <sbuisson@ddn.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Arshad Hussain <arshad.hussain@aeoncomputing.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>