Fortran: fix issue with I/O of array pointer [PR107968]

	PR fortran/107968

gcc/fortran/ChangeLog:

	* trans-io.cc (gfc_trans_transfer): Also scalarize I/O of section
	of an array pointer.

gcc/testsuite/ChangeLog:

	* gfortran.dg/implied_do_io_9.f90: New test.

(cherry picked from commit e3431c6fd4691d5a0c48ee78869e5f9a79f217c3)