fix(options): default of expanded option out of sync at startup

Problem:
set_options_default() expands `$VAR` in the value but not the stored
default. set_init_expand_env() then expands the value (already
expanded), sees no change, and leaves the default unexpanded, so `:set`
lists 'helpfile' as changed.

This was accidentally hidden until 211623c1388d because env var depended
on 'isident', which was not initialized at set_options_default() time.

Solution:
set_init_expand_env() expands the default, and sets both from it.

0 files changed, 0 insertions, 0 deletions