MCS: move HeaderType enum outside of class definition

Move functions which compute number of blocks or bits depending on
header type and corresponding enum outside of GprsCodingScheme
class. This will allows us to use standard libosmocore value_sting
functions in upcoming patches for IA Rest Octet encoding/decoding.

Change-Id: Id0873f85e1f16a72e17e7fbc4ad76b194917067f
diff --git a/src/gprs_bssgp_pcu.cpp b/src/gprs_bssgp_pcu.cpp
index f63fac3..7ac5ab1 100644
--- a/src/gprs_bssgp_pcu.cpp
+++ b/src/gprs_bssgp_pcu.cpp
@@ -26,6 +26,7 @@
 #include <tbf.h>
 #include <gprs_coding_scheme.h>
 #include <pdch.h>
+#include "coding_scheme.h"
 
 #define BSSGP_TIMER_T1	30	/* Guards the (un)blocking procedures */
 #define BSSGP_TIMER_T2	30	/* Guards the reset procedure */
@@ -607,7 +608,7 @@
 
 static uint32_t gprs_bssgp_max_leak_rate(GprsCodingScheme cs, int num_pdch)
 {
-	int bytes_per_rlc_block = cs.maxDataBlockBytes() * cs.numDataBlocks();
+	int bytes_per_rlc_block = cs.maxDataBlockBytes() * num_data_blocks(cs.headerTypeData());
 
 	/* n byte payload per 20ms */
 	return bytes_per_rlc_block * (1000 / 20) * num_pdch;