net: mvneta: select GENERIC_ALLOCATOR

We previously relied on GENERIC_ALLOCATOR to be selected by CONFIG_ARM,
but now we can compile-test the driver on other architectures that
don't select it:

drivers/net/built-in.o: In function `mvneta_bm_remove':
mvneta_bm.c:(.text+0x4ee35): undefined reference to `gen_pool_free'

This adds an explicit select for the part of the driver that has
the dependency.

Fixes: a0627f776a ("net: marvell: Allow drivers to be built with COMPILE_TEST")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/Kconfig

@@ -76,6 +76,7 @@ config MVNETA_BM
 	default y if MVNETA=y && MVNETA_BM_ENABLE!=n
 	default MVNETA_BM_ENABLE
 	select HWBM
+	select GENERIC_ALLOCATOR
 	help
 	  MVNETA_BM must not be 'm' if MVNETA=y, so this symbol ensures
 	  that all dependencies are met.