aarch64: Add support for Cortex-A78C

This patch adds support for -mcpu=cortex-a78c command line option.
For more information about this processor, see [0]:

[0] https://developer.arm.com/ip-products/processors/cortex-a/cortex-a78c

gas/ChangeLog

@@ -1,3 +1,9 @@
+2020-11-04  Przemyslaw Wirkus  <przemyslaw.wirkus@arm.com>
+
+	* config/tc-aarch64.c (aarch64_cpus): Add Cortex-A78C.
+	* doc/c-aarch64.texi: Document -mcpu=cortex-a78c.
+	* doc/NEWS: Update news.
+
 2020-11-19  Jozef Lawrynowicz  <jozef.l@mittosystems.com>
 
 	* testsuite/gas/elf/section22.d: Allow FreeBSD OSABI in readelf

gas/NEWS

@@ -11,7 +11,8 @@
 * When setting the link order attribute of ELF sections, it is now possible to
   use a numeric section index instead of symbol name.
 
-* Add support for Cortex-A78, Cortex-A78AE and Cortex-X1 for AArch64 and ARM.
+* Add support for Cortex-A78, Cortex-A78AE, Cortex-A78C and Cortex-X1 for
+  AArch64 and ARM.
   Add support for Cortex-R82, Neoverse V1, and Neoverse N2 for ARM.
 
 * Add support for ETMv4 (Embedded Trace Macrocell), ETE (Embedded Trace

gas/config/tc-aarch64.c

@@ -9039,6 +9039,15 @@ static const struct aarch64_cpu_option_table aarch64_cpus[] = {
                    | AARCH64_FEATURE_SSBS
                    | AARCH64_FEATURE_PROFILE),
    "Cortex-A78AE"},
+  {"cortex-a78c", AARCH64_FEATURE (AARCH64_ARCH_V8_2,
+                   AARCH64_FEATURE_DOTPROD
+                   | AARCH64_FEATURE_F16
+                   | AARCH64_FEATURE_FLAGM
+                   | AARCH64_FEATURE_PAC
+                   | AARCH64_FEATURE_PROFILE
+                   | AARCH64_FEATURE_RCPC
+                   | AARCH64_FEATURE_SSBS),
+   "Cortex-A78C"},
   {"ares", AARCH64_FEATURE (AARCH64_ARCH_V8_2,
 				  AARCH64_FEATURE_RCPC | AARCH64_FEATURE_F16
 				  | AARCH64_FEATURE_DOTPROD

gas/doc/c-aarch64.texi

@@ -70,6 +70,7 @@ on the target processor.  The following processor names are recognized:
 @code{cortex-a77},
 @code{cortex-a78},
 @code{cortex-a78ae},
+@code{cortex-a78c},
 @code{ares},
 @code{exynos-m1},
 @code{falkor},