edge: Get EGPRS multislot class

The EGPRS MS class ist contained in the MS_RA_capability information.
Its presence indicates, that the MS is able (and willing) to use
EGPRS.

This commit implements basic support for retrieving, storing, and
showing it in the VTY. The information is stored in the MS object.

Sponsored-by: On-Waves ehf
diff --git a/src/decoding.cpp b/src/decoding.cpp
index fce8124..d4f014b 100644
--- a/src/decoding.cpp
+++ b/src/decoding.cpp
@@ -83,6 +83,21 @@
 	return 0;
 }
 
+uint8_t Decoding::get_egprs_ms_class_by_capability(MS_Radio_Access_capability_t *cap)
+{
+	int i;
+
+	for (i = 0; i < cap->Count_MS_RA_capability_value; i++) {
+		if (!cap->MS_RA_capability_value[i].u.Content.Exist_Multislot_capability)
+			continue;
+		if (!cap->MS_RA_capability_value[i].u.Content.Multislot_capability.Exist_EGPRS_multislot_class)
+			continue;
+		return cap->MS_RA_capability_value[i].u.Content.Multislot_capability.EGPRS_multislot_class;
+	}
+
+	return 0;
+}
+
 /**
  * show_rbb needs to be an array with 65 elements
  * The index of the array is the bit position in the rbb