package/coreutils: drop gmp optional dependency

libgmp is included in coreutils (through bootstrap.conf) since bump to
version 9.0 in commit 2ee43bad85693d1c96e14f5b39ccb13a8982f50a and
https://git.savannah.gnu.org/cgit/coreutils.git/commit/?id=13046444888a7e96f48d28fdd5a6ffe03d4ab036:

configure: WARNING: unrecognized options: --disable-gtk-doc, --disable-gtk-doc-html, --disable-doc, --disable-docs, --disable-documentation, --with-xmlto, --with-fop, --enable-ipv6, --enable-static, --enable-shared, --without-gmp

Fixes: 2ee43bad85693d1c96e14f5b39ccb13a8982f50a

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/coreutils/coreutils.mk

@@ -75,12 +75,6 @@ ifeq ($(BR2_PACKAGE_GETTEXT_PROVIDES_LIBINTL),y)
 COREUTILS_CONF_OPTS += --with-libintl-prefix=$(STAGING_DIR)/usr
 endif
 
-ifeq ($(BR2_PACKAGE_GMP),y)
-COREUTILS_DEPENDENCIES += gmp
-else
-COREUTILS_CONF_OPTS += --without-gmp
-endif
-
 ifeq ($(BR2_PACKAGE_LIBCAP),y)
 COREUTILS_DEPENDENCIES += libcap
 else