qcacld-3.0: Enable mobile router for SA515M in default config
In kernel 5.4, the arch name for sa515m is CONFIG_ARCH_SA515M, enable
mobile router for this arch in the default defconfig file. The
qca6490 uses the default defconfig, to support qca6490 in sa515m, this
change is required.
Change-Id: I1a26762f8453ea8028c626938599c1f7ddfd3ed4
CRs-Fixed: 3255024