Fix "make install" with a cross toolchain

We must be able to use a non-native strip executable, but not all
versions of 'install' support the --strip-program option (e.g.
OpenBSD). Accordingly, we can't use 'install -s', and we must run strip
separately.
Signed-off-by: NHollis Blanchard <hollis@penguinppc.org>
Cc: blauwirbel@gmail.com

Makefile.target

@@ -329,7 +329,10 @@ clean:
 
 install: all
 ifneq ($(PROGS),)
-	$(INSTALL) -m 755 $(STRIP_OPT) $(PROGS) "$(DESTDIR)$(bindir)"
+	$(INSTALL) -m 755 $(PROGS) "$(DESTDIR)$(bindir)"
+ifneq ($(STRIP),)
+	$(STRIP) $(patsubst %,"$(DESTDIR)$(bindir)/%",$(PROGS))
+endif
 endif
 
 # Include automatically generated dependency files

configure

@@ -80,6 +80,7 @@ make="make"
 install="install"
 objcopy="objcopy"
 ld="ld"
+strip="strip"
 helper_cflags=""
 libs_softmmu=""
 libs_tools=""
@@ -125,6 +126,7 @@ cc="${cross_prefix}${cc}"
 ar="${cross_prefix}${ar}"
 objcopy="${cross_prefix}${objcopy}"
 ld="${cross_prefix}${ld}"
+strip="${cross_prefix}${strip}"
 
 # default flags for all hosts
 QEMU_CFLAGS="-fno-strict-aliasing $QEMU_CFLAGS"
@@ -2227,7 +2229,7 @@ if test "$debug" = "yes" ; then
   echo "CONFIG_DEBUG_EXEC=y" >> $config_host_mak
 fi
 if test "$strip_opt" = "yes" ; then
-  echo "STRIP_OPT=-s" >> $config_host_mak
+  echo "STRIP=${strip}" >> $config_host_mak
 fi
 if test "$bigendian" = "yes" ; then
   echo "HOST_WORDS_BIGENDIAN=y" >> $config_host_mak