uClibc-ng: enable options required for printf testing

target/microblaze/uclibc-ng.config

@@ -180,8 +180,8 @@ UCLIBC_HAS_UCHAR=y
 # UCLIBC_HAS_LIBICONV is not set
 # UCLIBC_HAS_LIBINTL is not set
 # UCLIBC_HAS_LOCALE is not set
-# UCLIBC_HAS_HEXADECIMAL_FLOATS is not set
-# UCLIBC_HAS_GLIBC_CUSTOM_PRINTF is not set
+UCLIBC_HAS_HEXADECIMAL_FLOATS=y
+UCLIBC_HAS_GLIBC_CUSTOM_PRINTF=y
 UCLIBC_PRINTF_SCANF_POSITIONAL_ARGS=9
 # UCLIBC_HAS_STDIO_BUFSIZ_256 is not set
 # UCLIBC_HAS_STDIO_BUFSIZ_512 is not set