py/mkrules.mk: List hash files as byproducts.

These are produced by the "cat" command to makeqstrdefs.py, to allow it to
not update unchanged files.  cmake doesn't know about them and so they are
not removed on a "clean".

This triggered a bug in makeqstrdefs.py where it would not recreate a
deleted output file (which is removed by clean) if a stale hash file with a
valid hash still existed.

Listing them as byproducts will cause them to be deleted on clean.
Signed-off-by: Trent Piepho <tpiepho@gmail.com>

py/mkrules.cmake

@@ -99,6 +99,7 @@ add_custom_command(
 add_custom_command(
     OUTPUT ${MICROPY_QSTRDEFS_COLLECTED}
     COMMAND ${Python3_EXECUTABLE} ${MICROPY_PY_DIR}/makeqstrdefs.py cat qstr _ ${MICROPY_GENHDR_DIR}/qstr ${MICROPY_QSTRDEFS_COLLECTED}
+    BYPRODUCTS "${MICROPY_QSTRDEFS_COLLECTED}.hash"
     DEPENDS ${MICROPY_QSTRDEFS_SPLIT}
     VERBATIM
     COMMAND_EXPAND_LISTS
@@ -136,6 +137,7 @@ add_custom_command(
 add_custom_command(
     OUTPUT ${MICROPY_MODULEDEFS_COLLECTED}
     COMMAND ${Python3_EXECUTABLE} ${MICROPY_PY_DIR}/makeqstrdefs.py cat module _ ${MICROPY_GENHDR_DIR}/module ${MICROPY_MODULEDEFS_COLLECTED}
+    BYPRODUCTS "${MICROPY_MODULEDEFS_COLLECTED}.hash"
     DEPENDS ${MICROPY_MODULEDEFS_SPLIT}
     VERBATIM
     COMMAND_EXPAND_LISTS
@@ -161,6 +163,7 @@ add_custom_command(
 add_custom_command(
     OUTPUT ${MICROPY_ROOT_POINTERS_COLLECTED}
     COMMAND ${Python3_EXECUTABLE} ${MICROPY_PY_DIR}/makeqstrdefs.py cat root_pointer _ ${MICROPY_GENHDR_DIR}/root_pointer ${MICROPY_ROOT_POINTERS_COLLECTED}
+    BYPRODUCTS "${MICROPY_ROOT_POINTERS_COLLECTED}.hash"
     DEPENDS ${MICROPY_ROOT_POINTERS_SPLIT}
     VERBATIM
     COMMAND_EXPAND_LISTS