package/petitboot: add libxcrypt optional dependency

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

  checking for crypt in -lcrypt... no
  configure: error: in `/home/arbab/src/buildroot/output/build/petitboot-1.15':
  configure: error: shadow/crypt libs required

Signed-off-by: Reza Arbab <arbab@linux.ibm.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

package/petitboot/Config.in

@@ -14,6 +14,7 @@ config BR2_PACKAGE_PETITBOOT
 	# run-time dependencies
 	select BR2_PACKAGE_KEXEC if !BR2_PACKAGE_KEXEC_LITE_ARCH_SUPPORTS
 	select BR2_PACKAGE_KEXEC_LITE if BR2_PACKAGE_KEXEC_LITE_ARCH_SUPPORTS && !BR2_PACKAGE_KEXEC
+	select BR2_PACKAGE_LIBXCRYPT if BR2_TOOLCHAIN_USES_GLIBC
 	select BR2_PACKAGE_NVME if ( BR2_powerpc || BR2_powerpc64 || BR2_powerpc64le )
 	select BR2_PACKAGE_POWERPC_UTILS if ( BR2_powerpc || BR2_powerpc64 || BR2_powerpc64le )
 	help

package/petitboot/petitboot.mk

@@ -14,6 +14,7 @@ PETITBOOT_DEPENDENCIES = \
 	host-bison \
 	host-flex \
 	lvm2 \
+	$(if $(BR2_PACKAGE_LIBXCRYPT),libxcrypt) \
 	$(TARGET_NLS_DEPENDENCIES)
 PETITBOOT_LICENSE = GPL-2.0
 PETITBOOT_LICENSE_FILES = COPYING