scripts: Move Kconfig contents to cmd/Kconfig

On case-insensitive file systems we have collision between
scripts/kconfig/ directory and scripts/Kconfig file. This patch moves
scripts/Kcofnig contents to cmd/Kconfig to fix that.

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/Kconfig b/Kconfig
index 238fa3e..d951e9f 100644
--- a/Kconfig
+++ b/Kconfig
@@ -398,5 +398,3 @@
 source "lib/Kconfig"
 
 source "test/Kconfig"
-
-source "scripts/Kconfig"
diff --git a/cmd/Kconfig b/cmd/Kconfig
index 28c91ca..bc4f726 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -116,6 +116,9 @@
 
 source "cmd/fastboot/Kconfig"
 
+config BUILD_BIN2C
+	bool
+
 comment "Commands"
 
 menu "Info commands"
diff --git a/scripts/Kconfig b/scripts/Kconfig
deleted file mode 100644
index 2a2c18e..0000000
--- a/scripts/Kconfig
+++ /dev/null
@@ -1,2 +0,0 @@
-config BUILD_BIN2C
-	bool