Transceiver52M: Use independent noise vectors for each channel

Each ARFCN channel may be independently configureted and possibly on
separate hardware, so don't share a single vector for noise estimate
calculations. Allow a non-pointer based iterator so we can get away
with using the default copy constructor.

Signed-off-by: Thomas Tsou <tom@tsou.cc>
diff --git a/Transceiver52M/radioVector.cpp b/Transceiver52M/radioVector.cpp
index ead4481..d6fb742 100644
--- a/Transceiver52M/radioVector.cpp
+++ b/Transceiver52M/radioVector.cpp
@@ -74,10 +74,9 @@
 	return true;
 }
 
-noiseVector::noiseVector(size_t n)
+noiseVector::noiseVector(size_t size)
+	: std::vector<float>(size), itr(0)
 {
-	this->resize(n);
-	it = this->begin();
 }
 
 float noiseVector::avg()
@@ -95,10 +94,10 @@
 	if (!size())
 		return false;
 
-	if (it == this->end())
-		it = this->begin();
+	if (itr >= this->size())
+		itr = 0;
 
-	*it++ = val;
+	(*this)[itr++] = val;
 
 	return true;
 }