add octeon+ as an alias for octeon in GCC & binutils

In r208737 jmallett@ added support for the "mips64r2" architecture
and "octeon" CPU, and the saa/saad instructions.

Upstream binutils also added the "octeon+" CPU, and the saa/saad
instructions are only available in octeon+, not octeon.  Since our
base system tool chain already accepts saa/saad with -march=octeon,
just allow octeon+ as an alias.

This allows the use of octeon+ in kernel config files, for use with both
external tool chain and in-tree GCC/binutils.

PR:		216516
MFC after:	1 month
Sponsored by:	The FreeBSD Foundation

contrib/binutils/gas/config/tc-mips.c

@@ -15156,6 +15156,7 @@ static const struct mips_cpu_info mips_cpu_info_table[] =
 
   /* Cavium Networks Octeon CPU core */
   { "octeon",         0,      ISA_MIPS64R2,   CPU_OCTEON },
+  { "octeon+",        0,      ISA_MIPS64R2,   CPU_OCTEON },
 
   /* End marker */
   { NULL, 0, 0, 0 }

contrib/gcc/config/mips/mips.c

@@ -765,6 +765,7 @@ const struct mips_cpu_info mips_cpu_info_table[] = {
 
   /* MIPS64R2 */
   { "octeon", PROCESSOR_OCTEON, 65 },
+  { "octeon+", PROCESSOR_OCTEON, 65 },
 
   /* End marker */
   { 0, 0, 0 }

contrib/gcc/config/mips/mips.h

@@ -285,7 +285,10 @@ extern const struct mips_rtx_cost_data *mips_cost;
 								\
       macro = concat ((PREFIX), "_", (INFO)->name, NULL);	\
       for (p = macro; *p != 0; p++)				\
-	*p = TOUPPER (*p);					\
+	if (*p == '+')						\
+	  *p = 'P';						\
+	else							\
+	  *p = TOUPPER (*p);					\
 								\
       builtin_define (macro);					\
       builtin_define_with_value ((PREFIX), (INFO)->name, 1);	\