vmlinux.lds.h has ~45 occurrences of this general pattern:

  __start_foo = .;
  KEEP(*(foo))
  __stop_foo = .;

Reduce this pattern to a (group of 4) macros, and use them to reduce
linecount.  This was inspired by the codetag patchset.

no functional change.

CC: Suren Baghdasaryan <surenb@google.com>
CC: Kent Overstreet <kent.overstreet@linux.dev>
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Link: https://lore.kernel.org/r/20221022225637.1406715-2-jim.cromie@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>