module: Sync code of is_arm_mapping_symbol()

After commit 2e3a10a155 ("ARM: avoid ARM binutils leaking ELF local
symbols") and commit d6b732666a ("modpost: fix undefined behavior of
is_arm_mapping_symbol()"), many differences of is_arm_mapping_symbol()
exist in kernel/module/kallsyms.c and scripts/mod/modpost.c, just sync
the code to keep consistent.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>

kernel/module/kallsyms.c

@@ -251,8 +251,9 @@ static inline int is_arm_mapping_symbol(const char *str)
 {
 	if (str[0] == '.' && str[1] == 'L')
 		return true;
-	return str[0] == '$' && strchr("axtd", str[1]) &&
-	       (str[2] == '\0' || str[2] == '.');
+	return str[0] == '$' &&
+	       (str[1] == 'a' || str[1] == 'd' || str[1] == 't' || str[1] == 'x')
+	       && (str[2] == '\0' || str[2] == '.');
 }
 
 static const char *kallsyms_symbol_name(struct mod_kallsyms *kallsyms, unsigned int symnum)

scripts/mod/modpost.c

@@ -1114,6 +1114,8 @@ static int secref_whitelist(const struct sectioncheck *mismatch,
 
 static inline int is_arm_mapping_symbol(const char *str)
 {
+	if (str[0] == '.' && str[1] == 'L')
+		return true;
 	return str[0] == '$' &&
 	       (str[1] == 'a' || str[1] == 'd' || str[1] == 't' || str[1] == 'x')
 	       && (str[2] == '\0' || str[2] == '.');