Transceiver52M: Refactor RACH and normal burst detection

Both RACH and normal bursts are detected with the same approach of
midamble correlation combined with peak-to-average ratio. The
difference is the midamble placements and lengths. Thus, there is
no reason to have independent implementations.

This patch creates a common call burstDetect(), while leaving the
correlation window indexing in the original calls.

Signed-off-by: Thomas Tsou <tom@tsou.cc>
diff --git a/Transceiver52M/Transceiver.cpp b/Transceiver52M/Transceiver.cpp
index ad048ee..a5bbfc1 100644
--- a/Transceiver52M/Transceiver.cpp
+++ b/Transceiver52M/Transceiver.cpp
@@ -363,7 +363,7 @@
     float chanOffset;
     success = analyzeTrafficBurst(*vectorBurst,
 				  mTSC,
-				  3.0,
+				  5.0,
 				  mSPS,
 				  &amplitude,
 				  &TOA,
@@ -398,7 +398,7 @@
   else {
     // RACH burst
     success = detectRACHBurst(*vectorBurst,
-			      5.0,  // detection threshold
+			      6.0,
 			      mSPS,
 			      &amplitude,
 			      &TOA);