sim: drop use of bfd/configure.host

These settings might have made sense in darker compiler times, but I
think they're largely obsolete now.  Looking through the values that
get used in HDEFINES, it's quite limited, and configure itself should
handle them.  If we still need something, we can leverage standard
autoconf macros instead, after we get a clear user report.

TDEFINES was never set anywhere and was always empty, so prune that.

sim/arm/configure

@@ -681,7 +681,6 @@ PACKAGE
 C_DIALECT
 RANLIB
 AR
-HDEFINES
 CC_FOR_BUILD
 INSTALL_DATA
 INSTALL_SCRIPT
@@ -6905,7 +6904,15 @@ fi
 test -z "$AR" && AR=ar
 if test -n "$plugin_option"; then
   if $AR --help 2>&1 | grep -q "\--plugin"; then
-    AR="$AR $plugin_option"
+    touch conftest.c
+    $AR $plugin_option rc conftest.a conftest.c
+    if test "$?" != 0; then
+      { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: Failed: $AR $plugin_option rc" >&5
+$as_echo "$as_me: WARNING: Failed: $AR $plugin_option rc" >&2;}
+    else
+      AR="$AR $plugin_option"
+    fi
+    rm -f conftest.*
   fi
 fi
 test -z "$AR_FLAGS" && AR_FLAGS=cru
@@ -8565,7 +8572,6 @@ fi
 
 
 
-
 AR=${AR-ar}
 
 if test -n "$ac_tool_prefix"; then
@@ -12929,7 +12935,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 12932 "configure"
+#line 12938 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -13035,7 +13041,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 13038 "configure"
+#line 13044 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -13274,8 +13280,6 @@ CC="$lt_save_CC"
 
 
 
-. ${srcdir}/../../bfd/configure.host
-