Fix id of gcc toolchains to include the correct abi

Change-Id: Ibdccea90c1a234a5c4ddaed27f0d50cb3204f603
Reviewed-by: Tobias Hunger <tobias.hunger@nokia.com>

src/plugins/projectexplorer/gcctoolchain.cpp

@@ -341,6 +341,7 @@ void GccToolChain::setTargetAbi(const Abi &abi)
 
     updateSupportedAbis();
     m_targetAbi = abi;
+    updateId();
     toolChainUpdated();
 }