[PATCH v2 0/5] various: remove dead code

Remove various bits of dead code. Addresses feedback on the v1: https://lore.kernel.org/git/cover-0.6-00000000000-20211119T124420Z-avarab@gmail.com/

There's the minor commit message changes seen below, and the strbuf change has been ejected per Junio's request.

Ævar Arnfjörð Bjarmason (5):
  xdiff/xmacros.h: remove unused XDL_PTRFREE
  pack-bitmap-write: remove unused bitmap_reset() function
  object-store.h: remove unused has_sha1_file*()
  alloc.[ch]: remove alloc_report() function
  json-writer.[ch]: remove unused formatting functions

 alloc.c                                       | 19 ---------------
 alloc.h                                       |  1 -
 .../coccinelle/the_repository.pending.cocci   | 15 ------------
 ewah/bitmap.c                                 |  5 ----
 ewah/ewok.h                                   |  1 -
 json-writer.c                                 | 24 -------------------
 json-writer.h                                 |  3 ---
 object-store.h                                |  4 ----
 xdiff/xmacros.h                               |  1 -
 9 files changed, 73 deletions(-)

Range-diff against v1:
1:  32bb8ad4de0 ! 1:  1e7e6d8d482 xdiff/xmacros.h: remove unused XDL_PTRFREE
    @@ Commit message
         generator, 2006-03-24), but none of the xdiff code uses it, it uses
         xdl_free() directly.
     
    +    If we need its functionality again we'll use the FREE_AND_NULL() macro
    +    added in 481df65f4f7 (git-compat-util: add a FREE_AND_NULL() wrapper
    +    around free(ptr); ptr = NULL, 2017-06-15).
    +
         Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
     
      ## xdiff/xmacros.h ##
2:  826027d2cd5 ! 2:  c9026af8953 pack-bitmap-write: remove unused bitmap_reset() function
    @@ Commit message
     
         This function hasn't been used since 449fa5ee069 (pack-bitmap-write:
         ignore BITMAP_FLAG_REUSE, 2020-12-08), which was a cleanup commit
    -    intending to get rid of the code around the resetting of bitmaps.
    +    intending to get rid of the code around the reusing of bitmaps.
     
         Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
     
3:  62ed0ec6077 = 3:  6d0ca249001 object-store.h: remove unused has_sha1_file*()
4:  bd8aa9b1554 = 4:  672bdffde83 alloc.[ch]: remove alloc_report() function
5:  642eec3d77c < -:  ----------- strbuf: remove unused istarts_with() function
6:  e14ee1f8c47 = 5:  818f1a46d66 json-writer.[ch]: remove unused formatting functions