scripts/mod/modpost: Fix cross-build race

Define CONFIG_MODPOST_ELFCONFIG macro to specify cross-build
elfconfig.h instead of copying header during build.

Signed-off-by: Haris Okanovic <haris.okanovic@ni.com>
Acked-by: Julia Cartwright <julia.cartwright@ni.com>
Natinst-ReviewBoard-ID: 292369

scripts/mod/Makefile

@@ -36,8 +36,7 @@ KBUILD_OUTPUT=$(CURDIR)
 endif
 
 $(patsubst %,$(obj)/$(TGTPRE)%,$(modpost-objs)): $(KBUILD_SRC)/$(src)/$(TGTPRE)elfconfig.h | $(obj)/modpost
-	$(Q)cp -f $(KBUILD_SRC)/$(src)/$(TGTPRE)elfconfig.h $(KBUILD_OUTPUT)/$(obj)/elfconfig.h
-	$(Q)$(CC) $(TGT_EXTRACFLAGS) $(CFLAGS) -I$(KBUILD_OUTPUT)/$(obj)  -c -o $@ $(KBUILD_SRC)/$(subst $(TGTPRE),,$(subst .o,.c,$@))
+	$(Q)$(CC) $(TGT_EXTRACFLAGS) $(CFLAGS) -I$(KBUILD_OUTPUT)/$(obj) -DCONFIG_MODPOST_ELFCONFIG="\"$(TGTPRE)elfconfig.h\"" -c -o $@ $(KBUILD_SRC)/$(subst $(TGTPRE),,$(subst .o,.c,$@))
 
 $(obj)/$(tgtmodpost) : $(patsubst %,$(obj)/$(TGTPRE)%,$(modpost-objs))
 	$(Q)$(CC) $(TGT_EXTRACFLAGS) $(CFLAGS) -o $@ $^

scripts/mod/modpost.h

@@ -10,7 +10,11 @@
 #include <unistd.h>
 #include <elf.h>
 
+#if defined(CONFIG_MODPOST_ELFCONFIG)
+#include CONFIG_MODPOST_ELFCONFIG
+#else
 #include "elfconfig.h"
+#endif
 
 /* On BSD-alike OSes elf.h defines these according to host's word size */
 #undef ELF_ST_BIND