KM: add CONFIG_KM_COMMON_ETH_INIT for km common eth init

This must be defined by a board support file that want to use the
keymile common.c board_eth_init function that requires ethernet_present
to be defined.

Currently all the km architectures use it but the kmp204x architecture
later supported in this series does use another board_eth_init function
and thus does not define it.

Signed-off-by: Valentin Longchamp <valentin.longchamp@keymile.com>

board/keymile/common/common.c

@@ -142,6 +142,7 @@ void i2c_init_board(void)
 }
 #endif
 
+#if defined(CONFIG_KM_COMMON_ETH_INIT)
 int board_eth_init(bd_t *bis)
 {
 	if (ethernet_present())
@@ -149,6 +150,7 @@ int board_eth_init(bd_t *bis)
 
 	return -1;
 }
+#endif
 
 /*
  * do_setboardid command

include/configs/km/km-powerpc.h

@@ -17,6 +17,9 @@
 #define CONFIG_CMD_DTT
 #define CONFIG_JFFS2_CMDLINE
 
+/* standard km ethernet_present for piggy */
+#define CONFIG_KM_COMMON_ETH_INIT
+
 /* EEprom support 24C08, 24C16, 24C64 */
 #define CONFIG_SYS_I2C_MULTI_EEPROMS
 #define CONFIG_SYS_EEPROM_PAGE_WRITE_ENABLE

include/configs/km/km_arm.h

@@ -164,6 +164,7 @@
 #define CONFIG_MVGBE_PORTS	{1, 0}	/* enable port 0 only */
 #define CONFIG_PHY_BASE_ADR	0
 #define CONFIG_ENV_OVERWRITE	/* ethaddr can be reprogrammed */
+#define CONFIG_KM_COMMON_ETH_INIT /* standard km ethernet_present for piggy */
 
 /*
  * UBI related stuff