[PATCH][GAS][AArch64] Update Cortex-X1 feature flags

This is feature flags update for Cortex-X1 CPU.
For more information about this processor, see [0].

[0] : https://www.arm.com/products/cortex-x

gas/ChangeLog:

2020-10-05  Przemyslaw Wirkus  <przemyslaw.wirkus@arm.com>

	* config/tc-aarch64.c: Update Cortex-X1 feature flags.

gas/config/tc-aarch64.c

@@ -9011,8 +9011,12 @@ static const struct aarch64_cpu_option_table aarch64_cpus[] = {
 			      AARCH64_FEATURE_CRC), "APM X-Gene 2"},
   {"cortex-r82", AARCH64_ARCH_V8_R, "Cortex-R82"},
   {"cortex-x1", AARCH64_FEATURE (AARCH64_ARCH_V8_2,
-                AARCH64_FEATURE_DOTPROD | AARCH64_FEATURE_PROFILE),
-  "Cortex-X1"},
+                AARCH64_FEATURE_F16
+                | AARCH64_FEATURE_RCPC
+                | AARCH64_FEATURE_DOTPROD
+                | AARCH64_FEATURE_SSBS
+                | AARCH64_FEATURE_PROFILE),
+                "Cortex-X1"},
   {"generic", AARCH64_ARCH_V8, NULL},
 
   {NULL, AARCH64_ARCH_NONE, NULL}