drop _ from mp_version_to_mpy_abi_version()

Author: dlech

mpy_cross_multi/__init__.py

@@ -1,7 +1,7 @@
 from semver.version import Version
 
 
-def _mp_version_to_mpy_abi_version(mp_ver: Version) -> str:
+def mp_version_to_mpy_abi_version(mp_ver: Version) -> str:
     """
     Convert MicroPython version to mpy-cross ABI version.
 

mpy_cross_multi/__main__.py

@@ -5,7 +5,7 @@
 
 from semver.version import Version
 
-from . import _mp_version_to_mpy_abi_version
+from mpy_cross_multi import mp_version_to_mpy_abi_version
 
 
 def _run():
@@ -46,7 +46,7 @@ def _run():
         sys.exit(1)
 
     try:
-        abi = _mp_version_to_mpy_abi_version(mp_semver)
+        abi = mp_version_to_mpy_abi_version(mp_semver)
     except NotImplementedError:
         print(
             f"Error: targeting MicroPython v{mp_semver} is not supported",