kconfig: remove unneeded dependency on !SPL_BUILD

Now CONFIG_SPL_BUILD is not defined in Kconfig, so
"!depends on SPL_BUILD" and "if !SPL_BUILD" are redundant.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
diff --git a/board/phytec/pcm051/Kconfig b/board/phytec/pcm051/Kconfig
index 65094cf..bb98715 100644
--- a/board/phytec/pcm051/Kconfig
+++ b/board/phytec/pcm051/Kconfig
@@ -13,12 +13,12 @@
 	default "pcm051"
 
 config DM
-	default y if !SPL_BUILD
+	default y
 
 config DM_GPIO
-	default y if !SPL_BUILD
+	default y
 
 config DM_SERIAL
-	default y if !SPL_BUILD
+	default y
 
 endif