genksyms: Handle string literals with spaces in reference files

BugLink: http://bugs.launchpad.net/bugs/1745263

commit a78f70e8 upstream.

The reference files use spaces to separate tokens, however, we must
preserve spaces inside string literals. Currently the only case in the
tree is struct edac_raw_error_desc in <linux/edac.h>:

$ KBUILD_SYMTYPES=1 make -s drivers/edac/amd64_edac.symtypes
$ mv drivers/edac/amd64_edac.{symtypes,symref}
$ KBUILD_SYMTYPES=1 make -s drivers/edac/amd64_edac.symtypes
drivers/edac/amd64_edac.c:527: warning: amd64_get_dram_hole_info: modversion changed because of changes in struct edac_raw_error_desc
Signed-off-by: Michal Marek <mmarek@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

scripts/genksyms/genksyms.c

@@ -423,13 +423,15 @@ static struct string_list *read_node(FILE *f)
 	struct string_list node = {
 		.string = buffer,
 		.tag = SYM_NORMAL };
-	int c;
+	int c, in_string = 0;
 
 	while ((c = fgetc(f)) != EOF) {
-		if (c == ' ') {
+		if (!in_string && c == ' ') {
 			if (node.string == buffer)
 				continue;
 			break;
+		} else if (c == '"') {
+			in_string = !in_string;
 		} else if (c == '\n') {
 			if (node.string == buffer)
 				return NULL;