cleanup: improve tag processing

cleanup: improve tag processing

Boolean algebra changes for process_each_lv_in_vg().

1st.
Drop process_lv variable since it's not needed.

2nd.
process_lv was always initilized to 0 - so the condition was always true.
It the condition (!tags_supplied && !lvargs_supplied) evaluates as "true",
process_all is already set to 1, so skip vg tags evaluation.

3rd.
Move check for matching lv name in the front of lv tags check
since this check can't be skipped for lvargs_matched counter.
If this filter evaluates to true, skip lv tags evaluation.