systemd-machine-units: update LIC_FILES_CHKSUM

Fixed:
WARNING: systemd-machine-units-1.0-r19 do_populate_lic: ${COREBASE}/LICENSE is not a valid license file, please use '${COMMON_LICENSE_DIR}/MIT' for a MIT License file in LIC_FILES_CHKSUM. This will become an error in the future

(From OE-Core rev: f2c809b1fe8679892220a06044d9b4bf2c8ae849)

Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-core/systemd/systemd-machine-units_1.0.bb

@@ -1,7 +1,7 @@
 SUMMARY = "Machine specific systemd units"
 
 LICENSE = "MIT"
-LIC_FILES_CHKSUM = "file://${COREBASE}/LICENSE;md5=4d92cd373abda3937c2bc47fbc49d690"
+LIC_FILES_CHKSUM = "file://${COMMON_LICENSE_DIR}/MIT;md5=0835ade698e0bcf8506ecda2f7b4f302"
 
 PACKAGE_ARCH = "${MACHINE_ARCH}"