Merge pull request dotnet/coreclr#5240 from wateret/mscorlib-arm-softfp

Support CoreLib build for arm-softfp

Commit migrated from https://github.com/dotnet/coreclr/commit/469c1339c9146e89e909eb201c82fe737c8d1081

diff --cc src/coreclr/build.sh
index e86fc1f,6f38848..0e1f725
--- 1/src/coreclr/build.sh
--- 2/src/coreclr/build.sh
+++ b/src/coreclr/build.sh
@@@ -221,9 -232,9 +221,9 @@@ isMSBuildOnNETCoreSupported(
          elif [ "$__BuildOS" == "OSX" ]; then
              __isMSBuildOnNETCoreSupported=1
          fi
-     elif [ "$__BuildArch" == "arm" ] || [ "$__BuildArch" == "arm64" ] ; then
+     elif [ "$__BuildArch" == "arm" ] || [ "$__BuildArch" == "arm-softfp" ] || [ "$__BuildArch" == "arm64" ] ; then
          if [ "$__BuildOS" == "Linux" ]; then
 -            if [ "$__DistroName" == "ubuntu" ]; then
 +            if [ "$__DistroRid" == "ubuntu.14.04-x64" ]; then
                  __isMSBuildOnNETCoreSupported=1
              fi
          fi