Closes #6392.

To reduce firmware size, this PR uses argument validators where possible and consolidates and simplifies various error messages.

• I went through all the mp_raise calls, and used validators from argcheck.c to simplify the validation. A few new validators were added, building on keypad: support for vector and matrix key scanning #4891.
• Added mp_arg_error_invalid(qstr), which raises ValueError with the message "Invalid %q". This is useful many places, where there were previously more specialized but not necessarily more informative messages. Then also added raise_ValueError_invalid_pin() and raise_ValueError_invalid_pins(), which refactor mp_arg_error_invalid(MP_QSTR_pin) and mp_arg_error_invalid(MP_QSTR_pins), both of which are very common (a couple dozen uses each).
• extmod/vfs_fat.c: refactor multiple identical calls to mp_raise_OSError()
• ps2io: regularize using clock* instead of clk*, to make argument names and internal names more consistent.
• Shorten some mp_raise_NotImplementedError()
• Used %q args to refactor and share some messages.
• Use m_malloc_fail() instead of more chatty specialized messages which were not necessarily more helpful. Thanks @tannewt for pointing this routine out.
• PixelBuf.c: refactor some identical error messages to reduce code size.

I did not try to squeeze the last drop out of various _bleio messages, since we are not short on code space in those builds, and the savings would be minimal.

Some initially measured byte savings (current savings are a few bytes more than this due to further changes):

I think some of the larger differences here are because some builds are not using LTO.

The number of distinct messages in circuitpython.pot went from 1061 to 989.