turn abis_nm_debugp_foh() into a macro

this will avoid printing 'abis_nm.c' as the filename in the log, which
is pretty useless during debugging.  We want to know where
abis_nm_debugp_foh() is being used from, not where it is implemented.
diff --git a/include/osmocom/gsm/abis_nm.h b/include/osmocom/gsm/abis_nm.h
index 320ac3e..e2b941f 100644
--- a/include/osmocom/gsm/abis_nm.h
+++ b/include/osmocom/gsm/abis_nm.h
@@ -30,7 +30,17 @@
 const char *abis_nm_opstate_name(uint8_t os);
 const char *abis_nm_avail_name(uint8_t avail);
 const char *abis_nm_test_name(uint8_t test);
-void abis_nm_debugp_foh(int ss, struct abis_om_fom_hdr *foh);
+
+/*! \brief write a human-readable OML header to the debug log
+ *  \param[in] ss Logging sub-system
+ *  \param[in] foh A-bis OML FOM header
+ */
+#define abis_nm_debugp_foh(ss, foh)					    \
+	DEBUGP(ss, "OC=%s(%02x) INST=(%02x,%02x,%02x) ",		    \
+		get_value_string(abis_nm_obj_class_names, foh->obj_class),  \
+		foh->obj_class, foh->obj_inst.bts_nr, foh->obj_inst.trx_nr, \
+		foh->obj_inst.ts_nr)
+
 
 int abis_nm_chcomb4pchan(enum gsm_phys_chan_config pchan);
 enum abis_nm_chan_comb abis_nm_pchan4chcomb(uint8_t chcomb);
diff --git a/src/gsm/abis_nm.c b/src/gsm/abis_nm.c
index f3f3a42..bb7008b 100644
--- a/src/gsm/abis_nm.c
+++ b/src/gsm/abis_nm.c
@@ -407,18 +407,6 @@
 	{ 0, NULL }
 };
 
-/*! \brief write a human-readable OML header to the debug log
- *  \param[in] ss Logging sub-system
- *  \param[in] foh A-bis OML FOM header
- */
-void abis_nm_debugp_foh(int ss, struct abis_om_fom_hdr *foh)
-{
-	DEBUGP(ss, "OC=%s(%02x) INST=(%02x,%02x,%02x) ",
-		get_value_string(abis_nm_obj_class_names, foh->obj_class),
-		foh->obj_class, foh->obj_inst.bts_nr, foh->obj_inst.trx_nr,
-		foh->obj_inst.ts_nr);
-}
-
 static const enum abis_nm_chan_comb chcomb4pchan[] = {
 	[GSM_PCHAN_NONE]	= 0xff,
 	[GSM_PCHAN_CCCH]	= NM_CHANC_mainBCCH,
@@ -452,4 +440,14 @@
 	return GSM_PCHAN_NONE;
 }
 
+/* this is just for compatibility reasons, it is now a macro */
+#undef abis_nm_debugp_foh
+void abis_nm_debugp_foh(int ss, struct abis_om_fom_hdr *foh)
+{
+	DEBUGP(ss, "OC=%s(%02x) INST=(%02x,%02x,%02x) ",
+		get_value_string(abis_nm_obj_class_names, foh->obj_class),
+		foh->obj_class, foh->obj_inst.bts_nr, foh->obj_inst.trx_nr,
+		foh->obj_inst.ts_nr);
+}
+
 /*! @} */