powerpc/powernv: Add AST graphics driver to powernv_defconfig

Most current OpenPOWER platforms have an AST BMC, so add graphics
support via the AST DRM driver.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/configs/powernv_defconfig

@@ -186,7 +186,8 @@ CONFIG_IPMI_DEVICE_INTERFACE=y
 CONFIG_IPMI_POWERNV=y
 CONFIG_RAW_DRIVER=y
 CONFIG_MAX_RAW_DEVS=1024
-CONFIG_FB=y
+CONFIG_DRM=y
+CONFIG_DRM_AST=y
 CONFIG_FIRMWARE_EDID=y
 CONFIG_FB_OF=y
 CONFIG_FB_MATROX=y
@@ -197,7 +198,6 @@ CONFIG_FB_RADEON=y
 CONFIG_FB_IBM_GXT4500=y
 CONFIG_LCD_PLATFORM=m
 # CONFIG_VGA_CONSOLE is not set
-CONFIG_FRAMEBUFFER_CONSOLE=y
 CONFIG_LOGO=y
 CONFIG_HID_GYRATION=y
 CONFIG_HID_PANTHERLORD=y