ANDROID: virt: gunyah: Move arch_is_gh_guest under RM probe

Some Qualcomm firmwares may crash on the "Call UID" query to hypervisor.
This call is made to check which hypervisor implmenetation Linux may be
a guest under. Move this check under the Gunyah RM driver probe so that
it is only made when Gunyah is definitely present.

This patch is destined for version 12 of the Gunyah patches posted to
kernel.org.

https://lore.kernel.org/all/20230304010632.2127470-1-quic_eberman@quicinc.com/



Bug: 268234781
Reported-by: Amit Pundir <amit.pundir@linaro.org>
Change-Id: I17499344b3b3f992cf93d99da9a0b9d16434602c
Signed-off-by: Elliot Berman <quic_eberman@quicinc.com>