lib: sbi: Replace test-and-set locks by ticket locks

Replace the test-and-set spinlock implementation with ticket locks
in order to get fairness (in form of FIFO order).

The implementation uses a 32-bit wide struct, which consists of
two 16-bit counters (owner and next). This is inspired by similar
spinlock implementations on other architectures.
This allows that the code works for both, RV32 and RV64.

Signed-off-by: Christoph Muellner <cmuellner@linux.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>