meson, configure: move --interp-prefix to meson

This is the last CONFIG_* entry in config-host.mak that had to be
special cased.

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/scripts/meson-buildoptions.sh b/scripts/meson-buildoptions.sh
index 3a86dd7..59c4a27 100644
--- a/scripts/meson-buildoptions.sh
+++ b/scripts/meson-buildoptions.sh
@@ -41,6 +41,8 @@
   printf "%s\n" '                           Set available tracing backends [log] (choices:'
   printf "%s\n" '                           dtrace/ftrace/log/nop/simple/syslog/ust)'
   printf "%s\n" '  --iasl=VALUE             Path to ACPI disassembler'
+  printf "%s\n" '  --interp-prefix=VALUE    where to find shared libraries etc., use %M for'
+  printf "%s\n" '                           cpu name [/usr/gnemul/qemu-%M]'
   printf "%s\n" '  --sphinx-build=VALUE     Use specified sphinx-build for building document'
   printf "%s\n" '  --tls-priority=VALUE     Default TLS protocol/cipher priority string'
   printf "%s\n" '                           [NORMAL]'
@@ -252,6 +254,7 @@
     --disable-iconv) printf "%s" -Diconv=disabled ;;
     --enable-install-blobs) printf "%s" -Dinstall_blobs=true ;;
     --disable-install-blobs) printf "%s" -Dinstall_blobs=false ;;
+    --interp-prefix=*) quote_sh "-Dinterp_prefix=$2" ;;
     --enable-jack) printf "%s" -Djack=enabled ;;
     --disable-jack) printf "%s" -Djack=disabled ;;
     --enable-keyring) printf "%s" -Dkeyring=enabled ;;