edge: Add methods and operators to GprsCodingScheme

Add a few new operators and methods to support the use of
GprsCodingScheme instead of the plain integer currently used.

Sponsored-by: On-Waves ehf
diff --git a/src/tbf_dl.cpp b/src/tbf_dl.cpp
index 8bac99f..e805992 100644
--- a/src/tbf_dl.cpp
+++ b/src/tbf_dl.cpp
@@ -749,7 +749,7 @@
 		/* Get statistics for current CS */
 
 		/* TODO: Use GprsCodingScheme everywhere and remove cast */
-		if (rlc_data->cs != (GprsCodingScheme::Scheme)current_cs()) {
+		if (rlc_data->cs != GprsCodingScheme((GprsCodingScheme::Scheme)current_cs())) {
 			/* This block has already been encoded with a different
 			 * CS, so it doesn't help us to decide, whether the
 			 * current CS is ok. Ignore it. */