Fix MSVC generator errors about generate_nativeexec
Fix MSVC generator errors about generate_nativeexec

We have splitfile asm targets for nativeexec.c and nativexec.appdll.c,
so I'm using NAME instead of NAME_WE to distinguish them.

Review URL: https://codereview.appspot.com/7388062

git-svn-id: ed337ca7cdb08c0ba29d8fe58632bb7686892c2d@1948 49cc7528-f6fd-11dd-9d1a-b59b2e1864b6

rnk/dynamorio,rnk/dynamorio,rnk/dynamorio,rnk/dynamorio,rnk/dynamorio