Revert "Fix Windows SDK build."

This reverts commit b8dd176441f6ba9527d24a5065d8225437fe39d5.

This wasn't the problem, and mingw doesn't even use _LARGEFILE_SOURCE. The real problem (using WIN32 instead of _WIN32 in external/llvm) is fixed now.

Change-Id: I2b708a006b530cb18d03b1425cd65edda35ee17e
1 file changed