mod/file2alias: make modalias generation safe for cross compiling

Use the target compiler to compute the offsets for the fields of the
device_id structures, so that it won't be broken by different alignments
between the host and target ABIs.

This also fixes missing endian corrections for some modaliases.

Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index ff36c50..11a8c30 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -2126,7 +2126,7 @@
 	struct ext_sym_list *extsym_iter;
 	struct ext_sym_list *extsym_start = NULL;
 
-	while ((opt = getopt(argc, argv, "i:I:e:cmsSo:awM:K:")) != -1) {
+	while ((opt = getopt(argc, argv, "i:I:e:msSo:awM:K:")) != -1) {
 		switch (opt) {
 		case 'i':
 			kernel_read = optarg;
@@ -2135,9 +2135,6 @@
 			module_read = optarg;
 			external_module = 1;
 			break;
-		case 'c':
-			cross_build = 1;
-			break;
 		case 'e':
 			external_module = 1;
 			extsym_iter =