sms: declare inline functions static to work with clang linker

- otherwise it results in no symbol found at module loading time

modules/sms/libsms_putsms.c

@@ -155,7 +155,7 @@ int make_pdu(struct sms_msg *msg, struct modem *mdm, char* pdu)
 
 
 /* search into modem reply for the sms id */
-inline int fetch_sms_id(char *answer)
+static inline int fetch_sms_id(char *answer)
 {
 	char *p;
 	int  id;

modules/sms/sms_funcs.c

@@ -370,7 +370,7 @@ error:
 
 
 
-inline int send_error(struct sms_msg *sms_messg, char *msg1_s, int msg1_len,
+static inline int send_error(struct sms_msg *sms_messg, char *msg1_s, int msg1_len,
 													char *msg2_s, int msg2_len)
 {
 	str  body;
@@ -398,7 +398,7 @@ error:
 
 
 
-inline unsigned int split_text(str *text, unsigned char *lens,int nice)
+static inline unsigned int split_text(str *text, unsigned char *lens,int nice)
 {
 	int  nr_chunks;
 	int  k,k1,len;

modules/sms/sms_report.c

@@ -112,7 +112,7 @@ void set_gettime_function(void)
 
 
 
-inline void free_report_cell(struct report_cell *cell)
+static inline void free_report_cell(struct report_cell *cell)
 {
 	if (!cell)
 		return;