sparc: fix interrupt enable/disable code

The manually written code was all wrong (missing branch delay slots,
wrong type of return instruction used, probably more bugs). Use the same
approach as x86 to have inline functions instead, which is much better
for performance and simpler to write.

Change-Id: Iac0fc814c15311658f983da58ac7f9d3edd75b81
Reviewed-on: https://review.haiku-os.org/c/haiku/+/3595
Reviewed-by: waddlesplash <waddlesplash@gmail.com>

sparc: interrupt management functions

Change-Id: Icc689cc0cc0075fbccdad23f77cfa53b1f32df3c
Reviewed-on: https://review.haiku-os.org/c/1107
Reviewed-by: waddlesplash <waddlesplash@gmail.com>