The sfc PMD was enabled for aarch32 which is 32-bit mode but has
cpu_family set to aarch64.
As sfc support only 64-bit system, it should be disabled for aarch32.
Updated meson file to disable sfc for aarch32 build.
Fixes: 141d287067 ("net/sfc: support aarch64 architecture")
Cc: stable@dpdk.org
Signed-off-by: Ruifeng Wang <ruifeng.wang@arm.com>