Fix mounting /lib/modules in initramfs, reduce initramfs size (#263)

kernel-xenlinux.spec

@@ -287,9 +287,8 @@ fi
 mkdir -p %buildroot/%vm_install_dir
 /sbin/dracut --nomdadmconf --nolvmconf \
     --kmoddir %buildroot/lib/modules/%kernelrelease \
-    --include %_sourcedir/vm-initramfs-pre-udev /pre-udev \
-    --include %_sourcedir/vm-initramfs-pre-pivot /pre-pivot \
-    --add-drivers xenblk \
+    --include %_sourcedir/vm-initramfs / \
+    -d "xenblk cdrom ext4 jbd2 crc16 dm_snapshot" \
     %buildroot/%vm_install_dir/initramfs %kernelrelease
 
 cp -p arch/x86/boot/vmlinuz %buildroot/%vm_install_dir/vmlinuz