Fortran: Fix runtime bogus diagnostic with ';'

	PR libfortran/121234

libgfortran/ChangeLog:

	* io/list_read.c (read_character): Add checks to bypass eating
	semicolons when reading strings with decimal mode 'point'
	(list_formatted_read_scalar): Likewise.

gcc/testsuite/ChangeLog:

	* gfortran.dg/pr121234.f90: New test.

(cherry picked from commit 3d496ed9a5821ae9188e5242c1e26eea80c4039f)