[cmake] pass GO_EXECUTABLE to llgo-go

Summary:
When calling llgo-go from the llvm_add_go_executable
cmake function, specify $GO_EXECUTABLE as the go
command to call. Without this, llgo-go searches $PATH
which may be inconsistent with $GO_EXECUTABLE.

Reviewers: pcc

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11290

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242749 91177308-0d34-0410-b5e6-96231b3b80d8

cmake/modules/AddLLVM.cmake

@@ -825,7 +825,7 @@ function(llvm_add_go_executable binary pkgpath)
     endforeach(d)
     set(ldflags "${CMAKE_EXE_LINKER_FLAGS}")
     add_custom_command(OUTPUT ${binpath}
-      COMMAND ${CMAKE_BINARY_DIR}/bin/llvm-go "cc=${cc}" "cxx=${cxx}" "cppflags=${cppflags}" "ldflags=${ldflags}"
+      COMMAND ${CMAKE_BINARY_DIR}/bin/llvm-go "go=${GO_EXECUTABLE}" "cc=${cc}" "cxx=${cxx}" "cppflags=${cppflags}" "ldflags=${ldflags}"
               ${ARG_GOFLAGS} build -o ${binpath} ${pkgpath}
       DEPENDS llvm-config ${CMAKE_BINARY_DIR}/bin/llvm-go${CMAKE_EXECUTABLE_SUFFIX}
               ${llvmlibs} ${ARG_DEPENDS}