PR fortran/24892
* io/io.h (unit_access): Add ACCESS_APPEND.
* io/open.c (access_opt): Add APPEND value for ACCESS keyword.
(st_open): Use that new value to set the POSITION accordingly.
* gfortran.dg/open_access_append_1.f90: New test.
* gfortran.dg/open_access_append_2.f90: New test.
From-SVN: r107119