package/cups: add libxcrypt optional dependency

Fix the following build failure raised since bump of glibc to version
2.39 in commit b5680f53d60acf8ff6010082f873438a39bd5d97:

/home/buildroot/autobuild/run/instance-1/output-1/host/lib/gcc/arc-buildroot-linux-gnu/13.1.1/../../../../arc-buildroot-linux-gnu/bin/ld: auth.o: in function `cupsdAuthorize':
auth.c:(.text+0xdba): undefined reference to `crypt'

Fixes: b5680f53d60acf8ff6010082f873438a39bd5d97
 - http://autobuild.buildroot.org/results/39b72d4e14895f901590d7e3404f69b4573d2cd2

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

package/cups/Config.in

@@ -6,6 +6,7 @@ config BR2_PACKAGE_CUPS
 	depends on BR2_TOOLCHAIN_HAS_THREADS
 	# needs fork()
 	depends on BR2_USE_MMU
+	select BR2_PACKAGE_LIBXCRYPT if BR2_TOOLCHAIN_USES_GLIBC
 	help
 	  The Common Unix Printing System
 

package/cups/cups.mk

@@ -33,6 +33,7 @@ CUPS_CONFIG_SCRIPTS = cups-config
 CUPS_DEPENDENCIES = \
 	host-autoconf \
 	host-pkgconf \
+	$(if $(BR2_PACKAGE_LIBXCRYPT),libxcrypt) \
 	$(if $(BR2_PACKAGE_ZLIB),zlib)
 
 ifeq ($(BR2_PACKAGE_SYSTEMD),y)