rlc/edge: Consistently use uint16_t for BSNs and SSNs

Currently in some places uint8_t is being used to encode BSNs and
SSNs. This is inconsistent and (even worse) not enough for EPGRS
which uses an SNS of 2014.

This commit changes these to uint16_t.

Sponsored-by: On-Waves ehf
diff --git a/src/rlc.cpp b/src/rlc.cpp
index c733667..f6d6f4a 100644
--- a/src/rlc.cpp
+++ b/src/rlc.cpp
@@ -98,7 +98,7 @@
 	return (ssn - 1 - bitnum);
 }
 
-void gprs_rlc_dl_window::update(BTS *bts, char *show_rbb, uint8_t ssn,
+void gprs_rlc_dl_window::update(BTS *bts, char *show_rbb, uint16_t ssn,
 			uint16_t *lost, uint16_t *received)
 {
 	/* SSN - 1 is in range V(A)..V(S)-1 */