RISC-V: Replace .option rvc/norvc with .option arch, +c/-c.

Since the .option rvc/norvc directives are obsolete, replace them with
the new proposed diretives: .option arch, +c/-c.  And also reset the
riscv_opts.rvc flag for the .option arch directives.

gas/
	* config/tc-riscv.c (s_riscv_option): Reset the riscv_opts.rvc
	for the .option arch directives.
	* testsuite/gas/riscv/align-1.s: Replace the obsolete .option
	rvc/norvc with .option arch, +c/-c.
	* testsuite/gas/riscv/c-add-addi.s: Likewise.
	* testsuite/gas/riscv/c-nonzero-imm.s: Likewise.
	* testsuite/gas/riscv/c-nonzero-reg.s: Likewise.
	* testsuite/gas/riscv/c-zero-imm-64.s: Likewise.
	* testsuite/gas/riscv/c-zero-imm.s: Likewise.
	* testsuite/gas/riscv/c-zero-reg.s: Likewise.
	* testsuite/gas/riscv/ext.s: Likewise.
	* testsuite/gas/riscv/mapping-01.s: Likewise.
	* testsuite/gas/riscv/mapping-02.s: Likewise.
	* testsuite/gas/riscv/mapping-03.s: Likewise.
	* testsuite/gas/riscv/mapping-04.s: Likewise.
	* testsuite/gas/riscv/no-relax-align-2.s: Likewise.
	* testsuite/gas/riscv/shamt-32.s: Likewise.
	* testsuite/gas/riscv/shamt-64.s: Likewise.

gas/config/tc-riscv.c

@@ -3773,6 +3773,10 @@ s_riscv_option (int x ATTRIBUTE_UNUSED)
       if (ISSPACE (*name) && *name != '\0')
 	name++;
       riscv_update_subset (&riscv_rps_as, name);
+
+      riscv_set_rvc (false);
+      if (riscv_subset_supports (&riscv_rps_as, "c"))
+	riscv_set_rvc (true);
     }
   else if (strcmp (name, "push") == 0)
     {

gas/testsuite/gas/riscv/align-1.s

@@ -1,3 +1,3 @@
-	.option norvc
+	.option arch, -c
 	.align 2
 	.align 1

gas/testsuite/gas/riscv/c-add-addi.s

@@ -1,3 +1,3 @@
-.option rvc
+.option arch, +c
 addi a2, zero, 1
 add a0, zero, a1

gas/testsuite/gas/riscv/c-nonzero-imm.s

@@ -1,3 +1,3 @@
-	.option rvc
+	.option arch, +c
 	c.nop 0
 	c.nop 1

gas/testsuite/gas/riscv/c-nonzero-reg.s

@@ -1,3 +1,3 @@
-	.option rvc
+	.option arch, +c
 	c.addiw x0, 10
 	c.jr x0

gas/testsuite/gas/riscv/c-zero-imm-64.s

@@ -1,4 +1,4 @@
-	.option rvc
+	.option arch, +c
 	# These are valid instructions.
 	addiw a6,a6,0
 	c.addiw a7,0

gas/testsuite/gas/riscv/c-zero-imm.s

@@ -1,4 +1,4 @@
-	.option rvc
+	.option arch, +c
 	# These are valid instructions.
 	li a0,0
 	c.li a1,0

gas/testsuite/gas/riscv/c-zero-reg.s

@@ -1,4 +1,4 @@
-	.option rvc
+	.option arch, +c
 	# These are hints.
 	c.li x0, 1
 	c.lui x0, 2

gas/testsuite/gas/riscv/ext.s

@@ -1,5 +1,5 @@
 target:
-	.option norvc
+	.option arch, -c
 	zext.b	a0, a0
 	zext.h	a0, a0
 	sext.b	a0, a0
@@ -18,7 +18,7 @@ target:
 	sext.w	a1, a2
 .endif
 
-	.option rvc
+	.option arch, +c
 	zext.b	a0, a0
 	zext.h	a0, a0
 	sext.b	a0, a0

gas/testsuite/gas/riscv/mapping-01.s

@@ -1,4 +1,4 @@
-	.option norvc
+	.option arch, -c
 	.text
 	.global	funcA
 funcA:

gas/testsuite/gas/riscv/mapping-02.s

@@ -1,4 +1,4 @@
-	.option norvc
+	.option arch, -c
 	.text
 	.word	1
 	add	a0, a0, a0

gas/testsuite/gas/riscv/mapping-03.s

@@ -1,4 +1,4 @@
-	.option norvc
+	.option arch, -c
 	.text
 	add	a0, a0, a0
 	.long	0

gas/testsuite/gas/riscv/mapping-04.s

@@ -1,5 +1,5 @@
 	.text
-	.option	norvc
+	.option	arch, -c
 	.fill	2, 4, 0x1001
 	.byte	1
 	.word	0

gas/testsuite/gas/riscv/no-relax-align-2.s

@@ -1,5 +1,5 @@
 	.option norelax
-	.option rvc
+	.option arch, +c
 	.byte 0
 	.align 4
 	nop

gas/testsuite/gas/riscv/shamt-32.s

@@ -1,4 +1,4 @@
-	.option norvc
+	.option arch, -c
 	slli	a0, a0, 0
 	slli	a0, a0, 31
 	slli	a0, a0, 32
@@ -14,7 +14,7 @@
 	srai	a0, a0, 32
 	srai	a0, a0, 63
 
-	.option rvc
+	.option arch, +c
 	slli	a0, a0, 0
 	slli	a0, a0, 31
 	slli	a0, a0, 32

gas/testsuite/gas/riscv/shamt-64.s

@@ -1,4 +1,4 @@
-	.option norvc
+	.option arch, -c
 	slli	a0, a0, 0
 	slli	a0, a0, 31
 	slli	a0, a0, 32
@@ -29,7 +29,7 @@
 	sraiw	a0, a0, 32
 	sraiw	a0, a0, 63
 
-	.option rvc
+	.option arch, +c
 	slli	a0, a0, 0
 	slli	a0, a0, 31
 	slli	a0, a0, 32