config/arm: allow WFE to be enabled config time

Allow RTE_ARM_USE_WFE to be enabled at meson configuration
time by passing it via c_args instead of modifying
`config/arm/meson.build`.

Example usage:
 meson build -Dc_args='-DRTE_ARM_USE_WFE' \
	--cross-file config/arm/arm64_cn10k_linux_gcc

Signed-off-by: Pavan Nikhilesh <pbhagavatula@marvell.com>
Acked-by: Chengwen Feng <fengchengwen@huawei.com>
Acked-by: Ruifeng Wang <ruifeng.wang@arm.com>
Signed-off-by: 0-day Robot <robot@bytheb.org>

config/arm/meson.build

@@ -17,7 +17,9 @@ flags_common = [
         #    ['RTE_ARM64_MEMCPY_ALIGN_MASK', 0xF],
         #    ['RTE_ARM64_MEMCPY_STRICT_ALIGN', false],
 
-        ['RTE_ARM_USE_WFE', false],
+        # Enable use of ARM wait for event instruction.
+        # ['RTE_ARM_USE_WFE', false],
+
         ['RTE_ARCH_ARM64', true],
         ['RTE_CACHE_LINE_SIZE', 128]
 ]