intel/blorp_blit: Adjust blorp surface parameters for split blits

intel/blorp_blit: Adjust blorp surface parameters for split blits

If try_blorp_blit() previously returned that a blit was too large,
shrink_surface_params() will be used to update the surface parameters
for the smaller blit so the blit operation can proceed.

v2:
 * Use double instead of float. (Jason)

Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>