Convert CONFIG_SYS_BOOTPARAMS_LEN to Kconfig

This converts the following to Kconfig:
   CONFIG_SYS_BOOTPARAMS_LEN

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/r8a77995_draak_defconfig b/configs/r8a77995_draak_defconfig
index 1d73756..e2a7e5f 100644
--- a/configs/r8a77995_draak_defconfig
+++ b/configs/r8a77995_draak_defconfig
@@ -21,6 +21,7 @@
 CONFIG_USE_BOOTCOMMAND=y
 CONFIG_BOOTCOMMAND="tftp 0x48080000 Image; tftp 0x48000000 Image-r8a77995-draak.dtb; booti 0x48080000 - 0x48000000"
 CONFIG_DEFAULT_FDT_FILE="r8a77995-draak.dtb"
+CONFIG_SYS_MALLOC_BOOTPARAMS=y
 CONFIG_UPDATE_TFTP=y
 CONFIG_HUSH_PARSER=y
 CONFIG_SYS_MAXARGS=64