[PATCH] net: airoha: Fix MODULE_LICENSE to match SPDX GPL-2.0-only identifier

["Wayen.Yan" <win847@gmail.com>]

Both airoha_eth.c and airoha_npu.c declare SPDX-License-Identifier:
GPL-2.0-only but use MODULE_LICENSE("GPL"), which the kernel module
loader interprets as GPL-2.0+ (any GPL version). This mismatch causes
license compliance tools (FOSSology, ScanCode, etc.) to misidentify
the effective license as more permissive than intended.

Replace MODULE_LICENSE("GPL") with MODULE_LICENSE("GPL v2") to
align with the GPL-2.0-only SPDX identifier. Per include/linux/module.h,
"GPL v2" maps to GPL-2.0-only, matching the source files' declared
license.

Fixes: 23020f049327 ("net: airoha: Introduce ethernet support for EN7581 SoC")
Signed-off-by: Wayen <win847@gmail.com>
---
 drivers/net/ethernet/airoha/airoha_eth.c | 2 +-
 drivers/net/ethernet/airoha/airoha_npu.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/airoha/airoha_eth.c b/drivers/net/ethernet/airoha/airoha_eth.c
index 31cdb11cd7..960727957e 100644
--- a/drivers/net/ethernet/airoha/airoha_eth.c
+++ b/drivers/net/ethernet/airoha/airoha_eth.c
@@ -3333,6 +3333,6 @@ static struct platform_driver airoha_driver = {
 };
 module_platform_driver(airoha_driver);
 
-MODULE_LICENSE("GPL");
+MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Lorenzo Bianconi <lorenzo@kernel.org>");
 MODULE_DESCRIPTION("Ethernet driver for Airoha SoC");
diff --git a/drivers/net/ethernet/airoha/airoha_npu.c b/drivers/net/ethernet/airoha/airoha_npu.c
index 17dbdc8325..870d61fdd9 100644
--- a/drivers/net/ethernet/airoha/airoha_npu.c
+++ b/drivers/net/ethernet/airoha/airoha_npu.c
@@ -826,6 +826,6 @@ MODULE_FIRMWARE(NPU_EN7581_7996_FIRMWARE_DATA);
 MODULE_FIRMWARE(NPU_EN7581_7996_FIRMWARE_RV32);
 MODULE_FIRMWARE(NPU_AN7583_FIRMWARE_DATA);
 MODULE_FIRMWARE(NPU_AN7583_FIRMWARE_RV32);
-MODULE_LICENSE("GPL");
+MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Lorenzo Bianconi <lorenzo@kernel.org>");
 MODULE_DESCRIPTION("Airoha Network Processor Unit driver");
-- 
2.51.0