Correct MOZTOOLS_PATH

The proposed MOZTOOLS_PATH no longer seems to be correct, as the current MozillaBuild Package doesn't create either C:\mozilla-build\mozmake or C:\mozilla-build\yasm directories. mozmake.exe and yasm.exe do exist in C:\mozilla-build\bin, though.

Author: mcduke

README.md

@@ -39,7 +39,7 @@ Under Windows:
 
 3. Set the `MOZTOOLS_PATH` environment variable to point to the tools from the Mozilla Build Package:
 ```
-set MOZTOOLS_PATH=C:\mozilla-build\msys\bin;C:\mozilla-build\mozmake;C:\mozilla-build\yasm
+set MOZTOOLS_PATH=C:\mozilla-build\msys\bin;C:\mozilla-build\bin
 ```
 
 4. Download and install Clang for Windows (64 bit) from https://releases.llvm.org/download.html