lib: allow to build asn1 decoder and oid registry in SPL

This commit adds the options:
- SPL_ASN1_DECODER
- SPL_OID_REGISTRY

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Philippe Reynes <philippe.reynes@softathome.com>
diff --git a/lib/Makefile b/lib/Makefile
index 11b03d1..13e5d8f 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -17,7 +17,6 @@
 obj-$(CONFIG_CMD_DHRYSTONE) += dhry/
 obj-$(CONFIG_ARCH_AT91) += at91/
 obj-$(CONFIG_OPTEE_LIB) += optee/
-obj-$(CONFIG_ASN1_DECODER) += asn1_decoder.o
 obj-y += crypto/
 
 obj-$(CONFIG_AES) += aes.o
@@ -74,6 +73,7 @@
 obj-$(CONFIG_SHA256) += sha256.o
 obj-$(CONFIG_SHA512) += sha512.o
 obj-$(CONFIG_CRYPT_PW) += crypt/
+obj-$(CONFIG_$(SPL_)ASN1_DECODER) += asn1_decoder.o
 
 obj-$(CONFIG_$(SPL_)ZLIB) += zlib/
 obj-$(CONFIG_$(SPL_)ZSTD) += zstd/
@@ -135,9 +135,9 @@
 else
 # Main U-Boot always uses the full printf support
 obj-y += vsprintf.o strto.o
-obj-$(CONFIG_OID_REGISTRY) += oid_registry.o
 obj-$(CONFIG_SSCANF) += sscanf.o
 endif
+obj-$(CONFIG_$(SPL_)OID_REGISTRY) += oid_registry.o
 
 obj-y += abuf.o
 obj-y += date.o