RISC-V: Remove RV64E conflict

Since RV32E *and* RV64E are ratified, RV64E is no longer invalid.

This commit removes a restriction that prevents making base ISA with
reduced GPRs with XLEN > 32.

bfd/ChangeLog:

	* elfxx-riscv.c (riscv_parse_check_conflicts): Remove RV64E
	conflict since the ratified 'E' base ISAs include RV64E.

gas/ChangeLog:

	* testsuite/gas/riscv/march-fail-base-02.d: Removed.
	* testsuite/gas/riscv/march-fail-base-02.l: Removed.

Author: a4lg

bfd/elfxx-riscv.c

@@ -1941,13 +1941,6 @@ riscv_parse_check_conflicts (riscv_parse_subset_t *rps)
   int xlen = *rps->xlen;
   bool no_conflict = true;
 
-  if (riscv_lookup_subset (rps->subset_list, "e", &subset)
-      && xlen > 32)
-    {
-      rps->error_handler
-	(_("rv%d does not support the `e' extension"), xlen);
-      no_conflict = false;
-    }
   if (riscv_lookup_subset (rps->subset_list, "q", &subset)
       && (subset->major_version < 2 || (subset->major_version == 2
 					&& subset->minor_version < 2))