intel/brw: Make component_size() consistent between VGRF and FIXED_GRF

Change so the size rounds up to the next multiple of the horizontal stride like
is done for VGRF.  This was causing an inconsistency in regs_read() -- The original
component_size() calculation for FIXED_GRF excluded any padding at the end but it was
still being discounted by regs_read().

Suggested by Curro.

Fixes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/11069
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/29736>
2 files changed