mt76: Enable NPU support for Airoha AN7581 SoC

Airoha AN7581 SoC supports a Network Processor (NPU) to offload WiFi
traffic. Add the required bits to enable the support of it in the MT76
driver. This will be enabled by default if we are compiling for the
Airoha AN7581 SoC.

Signed-off-by: Lorenzo Bianconi <[email protected]>
[ improve commit title/description ]
Link: https://github.com/openwrt/openwrt/pull/20826
Signed-off-by: Christian Marangi <[email protected]>

package/kernel/mt76/Makefile

@@ -495,6 +495,12 @@ ifdef CONFIG_PACKAGE_kmod-mt7921e
 endif
 ifdef CONFIG_PACKAGE_kmod-mt7996e
   PKG_MAKE_FLAGS += CONFIG_MT7996E=m
+  ifdef CONFIG_TARGET_airoha_an7581
+    PKG_MAKE_FLAGS += CONFIG_MT76_NPU=y
+    PKG_MAKE_FLAGS += CONFIG_MT7996_NPU=y
+    NOSTDINC_FLAGS += -DCONFIG_MT76_NPU
+    NOSTDINC_FLAGS += -DCONFIG_MT7996_NPU
+  endif
 endif
 ifdef CONFIG_PACKAGE_kmod-mt7925-common
   PKG_MAKE_FLAGS += CONFIG_MT7925_COMMON=m