amd-xgbe: do not select NET_SELFTESTS when INET is disabled

AMD_XGBE currently selects NET_SELFTESTS unconditionally. Since select
does not honor dependencies, this can force-enable NET_SELFTESTS even
when INET is disabled (e.g. INET=n randconfig builds).

Fixes build issue when INET is disabled.

Fixes: 862a64c ("amd-xgbe: introduce support ethtool selftest")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202602030920.SWN7cwzT-lkp@intel.com/
Signed-off-by: Raju Rangoju <Raju.Rangoju@amd.com>
Link: https://patch.msgid.link/20260204150020.883639-1-Raju.Rangoju@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: RajuRangoju

drivers/net/ethernet/amd/Kconfig

@@ -165,7 +165,7 @@ config AMD_XGBE
 	select CRC32
 	select PHYLIB
 	select AMD_XGBE_HAVE_ECC if X86
-	select NET_SELFTESTS
+	imply NET_SELFTESTS
 	help
 	  This driver supports the AMD 10GbE Ethernet device found on an
 	  AMD SoC.