am335x: configs: Fix usb ether boot support

CONFIG_SPL_NET_VCI_STRING is available only with BOOTP. So if
CMD_DHCP is enabled for SPL in usb ether boot, it will not pass
the right vendor name and failing to download the right file.
Also all the net CMD_* are not required in SPL builds. So defining
these only for non-SPL builds.

Reported-by: Yan Liu <yan-liu@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Reviewed-by: Sekhar Nori <nsekhar@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/include/configs/ti_am335x_common.h b/include/configs/ti_am335x_common.h
index edbd820..4535b8c 100644
--- a/include/configs/ti_am335x_common.h
+++ b/include/configs/ti_am335x_common.h
@@ -28,6 +28,7 @@
 #endif
 #define CONFIG_SYS_NS16550_CLK		48000000
 
+#ifndef CONFIG_SPL_BUILD
 /* Network defines. */
 #define CONFIG_CMD_DHCP
 #define CONFIG_CMD_MII
@@ -38,9 +39,10 @@
 #define CONFIG_BOOTP_SUBNETMASK
 #define CONFIG_NET_RETRY_COUNT         10
 #define CONFIG_CMD_PING
-#define CONFIG_DRIVER_TI_CPSW		/* Driver for IP block */
 #define CONFIG_MII			/* Required in net/eth.c */
+#endif
 
+#define CONFIG_DRIVER_TI_CPSW		/* Driver for IP block */
 /*
  * RTC related defines. To use bootcount you must set bootlimit in the
  * environment to a non-zero value and enable CONFIG_BOOTCOUNT_LIMIT