soc/intel/broadwell/igd.c: Rename to gma.c

This makes comparisons against Haswell a bit simpler.

Change-Id: If1c937628f702c6765a5f36b6eaf4a3c3516359a
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/46323
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>

src/soc/intel/broadwell/Makefile.inc

@@ -28,7 +28,7 @@ ramstage-y += gpio.c
 romstage-y += gpio.c
 smm-y      += gpio.c
 ramstage-y += hda.c
-ramstage-y += igd.c
+ramstage-y += gma.c
 ramstage-y += iobp.c
 romstage-y += iobp.c
 ramstage-y += fadt.c