Get rid of class GprsCodingScheme

We have same kind of object splitted into two layers, in coding_scheme
and gprs_coding_scheme. Let's merge them together and get rid of the
class, which is not really useful because it's only a set of functions
operating on one enum value.

This change also fixes gcc 10.1.0 error about memseting a complex type
in rlc.h init().

Change-Id: Ie9ce2144ba9e8dbba9704d4e0000a2929e3e41df
diff --git a/src/encoding.cpp b/src/encoding.cpp
index a4a14dd..1805645 100644
--- a/src/encoding.cpp
+++ b/src/encoding.cpp
@@ -1107,11 +1107,11 @@
 	struct gprs_rlc_dl_header_egprs_3 *egprs3;
 	struct rlc_dl_header *gprs;
 	unsigned int e_fbi_header;
-	GprsCodingScheme cs = rlc->cs;
+	enum CodingScheme cs = rlc->cs;
 	unsigned int offs;
 	unsigned int bsn_delta;
 
-	switch(cs.headerTypeData()) {
+	switch(mcs_header_type(cs)) {
 	case HEADER_GPRS_DATA:
 		gprs = static_cast<struct rlc_dl_header *>
 			((void *)data);
@@ -1595,7 +1595,7 @@
  * \return the state of the rlc/mac like if there is more space for another chunk
  */
 Encoding::AppendResult Encoding::rlc_data_to_dl_append(
-	struct gprs_rlc_data_block_info *rdbi, GprsCodingScheme cs,
+	struct gprs_rlc_data_block_info *rdbi, enum CodingScheme cs,
 	gprs_llc *llc, int *offset, int *num_chunks,
 	uint8_t *data_block, bool is_final, int *count_payload)
 {