Fix Monitor ID bitmask

The bitmask used to separate the MonitorID field from everything else in
the BeamMonitor packets was off by one bit.  Since the MonitorID field
is actually the top 10 bits the mask wasn't even needed (just a right
shift operation).

Refs #9563

Code/Mantid/Framework/LiveData/src/ADARA/ADARAPackets.cpp

@@ -266,7 +266,6 @@ BeamMonitorPkt::BeamMonitorPkt(const BeamMonitorPkt &pkt) :
     Packet(pkt), m_fields((const uint32_t *)payload()), m_sectionStartIndex(0)
 {}
 
-#define MONITOR_ID_MASK  0xFFA00000  // upper 10 bits
 #define EVENT_COUNT_MASK 0x003FFFFF  // lower 22 bits
 bool BeamMonitorPkt::nextSection() const
 // Returns true if there is a next section.  False if there isn't.
@@ -295,7 +294,8 @@ bool BeamMonitorPkt::nextSection() const
 
 uint32_t BeamMonitorPkt::getSectionMonitorID() const
 {
-    return (m_fields[m_sectionStartIndex] & MONITOR_ID_MASK) >> 22;
+    // Monitor ID is the upper 10 bits
+    return (m_fields[m_sectionStartIndex] >> 22);
 }
 
 uint32_t BeamMonitorPkt::getSectionEventCount() const