ARM: multi_v7_defconfig: add Panfrost driver

With the goal of making it easier for CI services such as KernelCI to
run tests for it.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Olof Johansson <olof@lixom.net>

arch/arm/configs/multi_v7_defconfig

@@ -656,6 +656,7 @@ CONFIG_DRM_VC4=m
 CONFIG_DRM_ETNAVIV=m
 CONFIG_DRM_MXSFB=m
 CONFIG_DRM_PL111=m
+CONFIG_DRM_PANFROST=m
 CONFIG_FB_EFI=y
 CONFIG_FB_WM8505=y
 CONFIG_FB_SH_MOBILE_LCDC=y