yocto-bsp: include meta-intel.inc if emgd selected

yocto-bsp: include meta-intel.inc if emgd selected

With move of ia32-base to oe-core, the intel-specific variables were
split off into meta-intel.inc, which needs to be included when using
components present only in meta-intel.

In the case of i386, that's currently just emgd, so conditionally
include emgd if emgd is selected as the xserver choice.

(From meta-yocto rev: b9cc7ce3407d3bc3909e7cc57c8a1290cb84a58b)

Signed-off-by: Tom Zanussi <tom.zanussi@intel.com>
Signed-off-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>