Fix compilation on cygwin.

* conf/Makefile.common (STRIPFLAGS_KERNEL): Add -F elf32-i386 and
	-R .drectve on cygwin.
	* conf/i386-pc-cygwin-img-ld.sc: Merge rdata and pdata into data.
	* configure.ac: Use $(top_builddir) in TARGET_OBJ2ELF.
	(COND_CYGWIN): New condition.
	* grub-core/Makefile.am (%.mod): Set TARGET_OBJ2ELF.
	* grub-core/genmod.sh.in: Use ${TARGET_OBJ2ELF} and
	not @TARGET_OBJ2ELF@.
	* util/grub-pe2elf.c (write_symbol_table): Use pe_symtab->type and not
	type to determine whether aux is to be used.

grub-core/Makefile.am

@@ -303,7 +303,7 @@ platform_DATA += moddep.lst
 CLEANFILES += config.log syminfo.lst moddep.lst
 
 $(MOD_FILES): %.mod : genmod.sh moddep.lst %.module$(EXEEXT)
-	sh $^ $@
+	TARGET_OBJ2ELF=@TARGET_OBJ2ELF@ sh $^ $@
 platform_DATA += $(MOD_FILES)
 CLEANFILES += $(MOD_FILES)
 

grub-core/genmod.sh.in

@@ -52,8 +52,8 @@ fi
 rm -f $t1 $t2
 
 if test x@TARGET_APPLE_CC@ != x1; then
-	if ! test -z "@TARGET_OBJ2ELF@"; then
-	    ./@TARGET_OBJ2ELF@ $tmpfile || exit 1
+	if ! test -z "${TARGET_OBJ2ELF}"; then
+	    ./${TARGET_OBJ2ELF} $tmpfile || exit 1
 	fi
 	if test x@platform@ != xemu; then
 	    @STRIP@ --strip-unneeded \