Disable gcc-toolchain on the clangs that don't support it

etc/config/c++.amazon1204.properties

@@ -30,12 +30,10 @@ compiler.clang32.exe=/opt/gcc-explorer/clang-3.2/bin/clang++
 compiler.clang32.alias=/opt/clang-3.2/bin/clang++
 compiler.clang32.name=x86-64 clang 3.2
 compiler.clang32.intelAsm=-mllvm --x86-asm-syntax=intel
-compiler.clang32.options=--gcc-toolchain=/opt/gcc-explorer/gcc-6.2.0
 compiler.clang33.exe=/opt/gcc-explorer/clang-3.3/bin/clang++
 compiler.clang33.alias=/opt/clang-3.3/bin/clang++
 compiler.clang33.name=x86-64 clang 3.3
 compiler.clang33.intelAsm=-mllvm --x86-asm-syntax=intel
-compiler.clang33.options=--gcc-toolchain=/opt/gcc-explorer/gcc-6.2.0
 compiler.clang341.exe=/opt/gcc-explorer/clang+llvm-3.4.1-x86_64-unknown-ubuntu12.04/bin/clang++
 compiler.clang341.alias=/opt/clang+llvm-3.4.1-x86_64-unknown-ubuntu12.04/bin/clang++
 compiler.clang341.name=x86-64 clang 3.4.1