drm/i915: make array hw_engine_mask static, makes object smaller

drm/i915: make array hw_engine_mask static, makes object smaller

Don't populate the array hw_engine_mask on the stack but instead make it
static. Makes the object code smaller by 316 bytes.

Before:
   text	   data	    bss	    dec	    hex	filename
  34004	   4388	    320	  38712	   9738	gpu/drm/i915/gt/intel_reset.o

After:
   text	   data	    bss	    dec	    hex	filename
  33528	   4548	    320	  38396	   95fc	gpu/drm/i915/gt/intel_reset.o

(gcc version 9.2.1, amd64)

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20191007154151.23245-1-colin.king@canonical.com