README: Fix small typo, dfeault -> default.
@@ -199,7 +199,7 @@ options (like cross-compiling), the same set of options should be passed
to `make deplibs`. To actually enable/disable use of dependencies, edit
`ports/unix/mpconfigport.mk` file, which has inline descriptions of the options.
For example, to build SSL module (required for `upip` tool described above,
-and so enabled by dfeault), `MICROPY_PY_USSL` should be set to 1.
+and so enabled by default), `MICROPY_PY_USSL` should be set to 1.
For some ports, building required dependences is transparent, and happens
automatically. But they still need to be fetched with the `make submodules`
