Moved all bitvector code to seperate file

This is required to remove C++ from other code.
diff --git a/src/pcu_l1_if.cpp b/src/pcu_l1_if.cpp
index e5fbad9..352fc0d 100644
--- a/src/pcu_l1_if.cpp
+++ b/src/pcu_l1_if.cpp
@@ -139,19 +139,14 @@
 	msgb_free(msg);
 }
 
-void pcu_l1if_tx_agch(bitvec * block, int plen)
+void pcu_l1if_tx_agch(uint8_t *data)
 {
-	uint8_t data[23]; /* prefix PLEN */
-	
-	/* FIXME: why does OpenBTS has no PLEN and no fill in message? */
-	bitvec_pack(block, data + 1);
-	data[0] = (plen << 2) | 0x01;
 	pcu_tx_data_req(0, 0, PCU_IF_SAPI_AGCH, 0, 0, 0, data, 23);
 }
 
-void pcu_l1if_tx_pch(bitvec * block, int plen, char *imsi)
+void pcu_l1if_tx_pch(uint8_t *data, char *imsi)
 {
-	uint8_t data[23+3]; /* prefix PLEN */
+	uint8_t pch_data[23+3];
 
 	/* paging group */
 	if (!imsi || strlen(imsi) < 3)
@@ -161,8 +156,7 @@
 	data[1] = imsi[1];
 	data[2] = imsi[2];
 
-	bitvec_pack(block, data + 3+1);
-	data[3] = (plen << 2) | 0x01;
+	memcpy(pch_data + 3, data, 23);
 	pcu_tx_data_req(0, 0, PCU_IF_SAPI_PCH, 0, 0, 0, data, 23+3);
 }