target-lm32: add simple disassembler

Because binutils disassembler is based on libopcode, this is a rewrite from
scratch.

Signed-off-by: Michael Walle <michael@walle.cc>
diff --git a/configure b/configure
index 4ef5ec6..4b3adc9 100755
--- a/configure
+++ b/configure
@@ -3770,6 +3770,10 @@
     echo "CONFIG_IA64_DIS=y"  >> $config_target_mak
     echo "CONFIG_IA64_DIS=y"  >> $libdis_config_mak
   ;;
+  lm32)
+    echo "CONFIG_LM32_DIS=y"  >> $config_target_mak
+    echo "CONFIG_LM32_DIS=y"  >> $libdis_config_mak
+  ;;
   m68k)
     echo "CONFIG_M68K_DIS=y"  >> $config_target_mak
     echo "CONFIG_M68K_DIS=y"  >> $libdis_config_mak