src: use namespace prefix osmo_counter*

Summary of changes:

s/struct counter/struct osmo_counter/g
s/counter_inc/osmo_counter_inc/g
s/counter_get/osmo_counter_get/g
s/counter_reset/osmo_counter_reset/g
s/counter_alloc/osmo_counter_alloc/g
s/counter_free/osmo_counter_free
diff --git a/openbsc/src/libbsc/bsc_init.c b/openbsc/src/libbsc/bsc_init.c
index 0056bb0..8e62dac 100644
--- a/openbsc/src/libbsc/bsc_init.c
+++ b/openbsc/src/libbsc/bsc_init.c
@@ -275,9 +275,9 @@
 		LOGP(DMI, LOGL_ERROR, "Lost some E1 TEI link: %d %p\n", isd->link_type, trx);
 
 		if (isd->link_type == E1INP_SIGN_OML)
-			counter_inc(trx->bts->network->stats.bts.oml_fail);
+			osmo_counter_inc(trx->bts->network->stats.bts.oml_fail);
 		else if (isd->link_type == E1INP_SIGN_RSL)
-			counter_inc(trx->bts->network->stats.bts.rsl_fail);
+			osmo_counter_inc(trx->bts->network->stats.bts.rsl_fail);
 
 		/*
 		 * free all allocated channels. change the nm_state so the