net: Fix compiling SPL when fastboot is enabled

When fastboot is enabled in U-Boot proper and SPL_NET is enabled, we will
try to (unsuccessfully) reference it in SPL. Fix these linker errors by
conditioning on SPL_UDP/TCP_FUNCTION_FASTBOOT.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/net/Makefile b/net/Makefile
index 3e2d061..64ab7ec 100644
--- a/net/Makefile
+++ b/net/Makefile
@@ -27,8 +27,8 @@
 obj-$(CONFIG_CMD_RARP) += rarp.o
 obj-$(CONFIG_CMD_SNTP) += sntp.o
 obj-$(CONFIG_CMD_TFTPBOOT) += tftp.o
-obj-$(CONFIG_UDP_FUNCTION_FASTBOOT)  += fastboot_udp.o
-obj-$(CONFIG_TCP_FUNCTION_FASTBOOT)  += fastboot_tcp.o
+obj-$(CONFIG_$(SPL_TPL_)UDP_FUNCTION_FASTBOOT)  += fastboot_udp.o
+obj-$(CONFIG_$(SPL_TPL_)TCP_FUNCTION_FASTBOOT)  += fastboot_tcp.o
 obj-$(CONFIG_CMD_WOL)  += wol.o
 obj-$(CONFIG_PROT_UDP) += udp.o
 obj-$(CONFIG_PROT_TCP) += tcp.o
diff --git a/net/net.c b/net/net.c
index e6f61f0..8357f08 100644
--- a/net/net.c
+++ b/net/net.c
@@ -511,12 +511,12 @@
 			tftp_start_server();
 			break;
 #endif
-#if defined(CONFIG_UDP_FUNCTION_FASTBOOT)
+#if CONFIG_IS_ENABLED(UDP_FUNCTION_FASTBOOT)
 		case FASTBOOT_UDP:
 			fastboot_udp_start_server();
 			break;
 #endif
-#if defined(CONFIG_TCP_FUNCTION_FASTBOOT)
+#if CONFIG_IS_ENABLED(TCP_FUNCTION_FASTBOOT)
 		case FASTBOOT_TCP:
 			fastboot_tcp_start_server();
 			break;