cpufreq: amd-pstate: fix spdxcheck warnings for amd-pstate-ut.c

spdxcheck warnings: (new ones prefixed by >>)
>> drivers/cpufreq/amd-pstate-ut.c: 1:28 Invalid License ID:
GPL-1.0-or-later
   drivers/spi/spi-gxp.c: 1:35 Invalid token: =or-later

Signed-off-by: Meng Li <li.meng@amd.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

drivers/cpufreq/amd-pstate-ut.c

@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: GPL-1.0-or-later
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * AMD Processor P-state Frequency Driver Unit Test
  *