engine: Prefer standard algorithms

Minor refactor to reduce codebase size by using standard algorithm
functions.

src/engine/enginemaster.cpp

@@ -868,13 +868,10 @@ void EngineMaster::addChannel(EngineChannel* pChannel) {
 }
 
 EngineChannel* EngineMaster::getChannel(const QString& group) {
-    for (int i = 0; i < m_channels.size(); ++i) {
-        ChannelInfo* pChannelInfo = m_channels[i];
-        if (pChannelInfo->m_pChannel->getGroup() == group) {
-            return pChannelInfo->m_pChannel;
-        }
-    }
-    return nullptr;
+    const auto it = std::find_if(std::begin(m_channels), std::end(m_channels), [&](const auto* pChannelInfo) {
+        return (pChannelInfo->m_pChannel->getGroup() == group);
+    });
+    return (it != std::end(m_channels)) ? (*it)->m_pChannel : nullptr;
 }
 
 CSAMPLE_GAIN EngineMaster::getMasterGain(int channelIndex) const {
@@ -896,13 +893,10 @@ const CSAMPLE* EngineMaster::getOutputBusBuffer(unsigned int i) const {
 }
 
 const CSAMPLE* EngineMaster::getChannelBuffer(const QString& group) const {
-    for (int i = 0; i < m_channels.size(); ++i) {
-        const ChannelInfo* pChannelInfo = m_channels[i];
-        if (pChannelInfo->m_pChannel->getGroup() == group) {
-            return pChannelInfo->m_pBuffer;
-        }
-    }
-    return nullptr;
+    const auto it = std::find_if(std::begin(m_channels), std::end(m_channels), [&](const auto* pChannelInfo) {
+        return (pChannelInfo->m_pChannel->getGroup() == group);
+    });
+    return (it != std::end(m_channels)) ? (*it)->m_pBuffer : nullptr;
 }
 
 const CSAMPLE* EngineMaster::buffer(const AudioOutput& output) const {