w32: Fix broken out-of-tree builds (missing version.o)

Commit 0b516ef0 added version.o to all
executables, but broke out-of-tree builds: for those builds the pattern
rule %.o: %.rc from rules.mak does not match, so version.o was no longer
built.

Adding explicit build rules fixes this.
Reported-by: NMichael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: NStefan Weil <sw@weilnetz.de>
Tested-by: NMichael Roth <mdroth@linux.vnet.ibm.com>

Makefile

@@ -168,7 +168,9 @@ recurse-all: $(SUBDIR_RULES) $(ROMSUBDIR_RULES)
 bt-host.o: QEMU_CFLAGS += $(BLUEZ_CFLAGS)
 
 $(BUILD_DIR)/version.o: $(SRC_PATH)/version.rc $(BUILD_DIR)/config-host.h | $(BUILD_DIR)/version.lo
+	$(call quiet-command,$(WINDRES) -I$(BUILD_DIR) -o $@ $<,"  RC    version.o")
 $(BUILD_DIR)/version.lo: $(SRC_PATH)/version.rc $(BUILD_DIR)/config-host.h
+	$(call quiet-command,$(WINDRES) -I$(BUILD_DIR) -o $@ $<,"  RC    version.lo")
 
 Makefile: $(version-obj-y) $(version-lobj-y)