add support for latest blackarch distro (issue #654)

INSTALL/grub/grub.cfg

@@ -270,6 +270,8 @@ function distro_specify_initrd_file_phase2 {
         fi
     elif [ -f (loop)/blackarch/boot/x86_64/archiso.img ]; then 
         vt_linux_specify_initrd_file /blackarch/boot/x86_64/archiso.img
+    elif [ -f (loop)/blackarch/boot/x86_64/initramfs-linux.img ]; then 
+        vt_linux_specify_initrd_file /blackarch/boot/x86_64/initramfs-linux.img
         
     elif [ -f (loop)/install.amd/initrd.gz ]; then
         vt_linux_specify_initrd_file /live/initrd2.img
@@ -548,6 +550,8 @@ function uefi_linux_menu_func {
             elif [ -d (loop)/blackarch ]; then
                 if [ -f (loop)/blackarch/boot/x86_64/archiso.img ]; then
                     vt_add_replace_file $vtindex "EFI\\archiso\\archiso.img"
+                elif [ -f (loop)/blackarch/boot/x86_64/initramfs-linux.img ]; then
+                    vt_add_replace_file $vtindex "blackarch\\boot\\x86_64\\initramfs-linux.img"
                 fi
             elif [ -d (loop)/anarchy ]; then
                 if [ -f (loop)/anarchy/boot/x86_64/initramfs-linux.img ]; then