spl: Kconfig: migrate $(SPL_TPL_)LDSCRIPT to Kconfig

Now that we have split up SPL_LDSCRIPT into a SPL and TPL variant and
have started to use the TPL-variant for the RK3368, it's time to clean
up behind ourselves: move both variants into Kconfig and remove them
from the whitelist.

Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/common/spl/Kconfig b/common/spl/Kconfig
index 64f9e1f..3342c04 100644
--- a/common/spl/Kconfig
+++ b/common/spl/Kconfig
@@ -18,6 +18,16 @@
 
 if SPL
 
+config SPL_LDSCRIPT
+	string "Linker script for the SPL stage"
+	default "arch/$(ARCH)/cpu/u-boot-spl.lds"
+	depends on SPL
+	help
+	  The SPL stage will usually require a different linker-script
+	  (as it runs from a different memory region) than the regular
+	  U-Boot stage.	 Set this to the path of the linker-script to
+	  be used for SPL.
+
 config SPL_BOARD_INIT
 	bool "Call board-specific initialization in SPL"
 	help
@@ -707,6 +717,15 @@
 
 if TPL
 
+config TPL_LDSCRIPT
+        string "Linker script for the TPL stage"
+	depends on TPL
+	help
+	  The TPL stage will usually require a different linker-script
+	  (as it runs from a different memory region) than the regular
+	  U-Boot stage.  Set this to the path of the linker-script to
+	  be used for TPL.
+
 config TPL_BOOTROM_SUPPORT
         bool "Support returning to the BOOTROM (from TPL)"
 	help