Update documentation for indent-relative functions

* lisp/indent.el (indent-relative): Document what happens when there
  is no previous nonblank line.
* doc/lispref/text.texi (Relative Indent): Document
  indent-relative-first-indent-point instead of obsolete
  indent-relative-maybe. Fix documentation of which argument from
  'indent-relative' is used.

Bug#34858
1 job for master in 53 minutes and 24 seconds (queued for 5 seconds)
Status Job ID Name Coverage
  Test
failed #1236
test-all

00:53:24

 
Name Stage Failure
failed
test-all Test
make[2]: *** [check-doit] Error 1
Makefile:313: recipe for target 'check-doit' failed
make[2]: Leaving directory '/builds/emacs/emacs/test'
Makefile:288: recipe for target 'check-expensive' failed
make[1]: *** [check-expensive] Error 2
make[1]: Leaving directory '/builds/emacs/emacs/test'
Makefile:962: recipe for target 'check-expensive' failed
make: *** [check-expensive] Error 2
ERROR: Job failed: exit code 1