arm64: cpu_errata: include required headers

Without including psci.h and arm-smccc.h, we now get a build failure in
some configurations:

arch/arm64/kernel/cpu_errata.c: In function 'arm64_update_smccc_conduit':
arch/arm64/kernel/cpu_errata.c:278:10: error: 'psci_ops' undeclared (first use in this function); did you mean 'sysfs_ops'?

arch/arm64/kernel/cpu_errata.c: In function 'arm64_set_ssbd_mitigation':
arch/arm64/kernel/cpu_errata.c:311:3: error: implicit declaration of function 'arm_smccc_1_1_hvc' [-Werror=implicit-function-declaration]
   arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_2, state, NULL);
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm64/kernel/cpu_errata.c

@@ -16,6 +16,8 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <linux/arm-smccc.h>
+#include <linux/psci.h>
 #include <linux/types.h>
 #include <asm/cpu.h>
 #include <asm/cputype.h>