base-config: Enable DRM_FBDEV_EMULATION fro HDMI audio

With the 6.7.0-rc2 update preparation with the sof-kconfig generated config
we lost HDMI audio on all platforms.
It turned out that the reason for it is that DRM_FBDEV_EMULATION is no
longer enabled.
See the following commits:
bb6c4507fe82 ("drm: fix up fbdev Kconfig defaults")
a5ae331edb02b ("drm: Drop select FRAMEBUFFER_CONSOLE for DRM_FBDEV_EMULATION")
701d2054fa317 ("fbdev: Make support for userspace interfaces configurable")

and possibly more.

The connection is not clear, but we cannot afford to loose HDMI audio.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>

base-defconfig

@@ -77,6 +77,9 @@ CONFIG_FB=y
 CONFIG_FRAMEBUFFER_CONSOLE=y
 # add support for using the EFI framebuffer as console
 CONFIG_FB_EFI=y
+# FB emulation appears to be needed for HDMI audio (!) support and
+# it is not enabled default since 6.7.0-rc1
+CONFIG_DRM_FBDEV_EMULATION=y
 
 # sudo modprobe configs && zgrep SOF_DEBUG /proc/config.gz
 CONFIG_IKCONFIG=m