Merge pull request #376 from jungle-boogie/patch-1

gmake necessary on *BSD systems.

README.md

@@ -80,7 +80,7 @@ Once you have the repository cloned, there are multiple ways provided to build Z
 #### Makefile
 
 If your system is compatible with `make`, you can simply run `make` at the root directory.
-It will generate `zstd` within root directory.
+It will generate `zstd` within root directory. Use `gmake` on *BSD systems.
 
 Other available options include :
 - `make install` : create and install zstd binary, library and man page