configure: Merge riscv32 and riscv64 host architectures

The existing code for safe-syscall.inc.S will compile
without change for riscv32 and riscv64.  We may also
drop the meson.build stanza that merges them for tcg/.

Reviewed-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
diff --git a/configure b/configure
index 039467c..d57ad58 100755
--- a/configure
+++ b/configure
@@ -570,11 +570,7 @@
     cpu="s390"
   fi
 elif check_define __riscv ; then
-  if check_define _LP64 ; then
-    cpu="riscv64"
-  else
-    cpu="riscv32"
-  fi
+  cpu="riscv"
 elif check_define __arm__ ; then
   cpu="arm"
 elif check_define __aarch64__ ; then
@@ -587,7 +583,7 @@
 # Normalise host CPU name and set ARCH.
 # Note that this case should only have supported host CPUs, not guests.
 case "$cpu" in
-  ppc|ppc64|s390x|sparc64|x32|riscv32|riscv64)
+  ppc|ppc64|s390x|sparc64|x32|riscv)
   ;;
   ppc64le)
     ARCH="ppc64"