[GRASS-git] [OSGeo/grass] 4d4a00: libgis: Enable the C99 bool type (#1567)

[nilason]

  Branch: refs/heads/releasebranch_7_8
  Home:   https://github.com/OSGeo/grass
  Commit: 4d4a007dd2c6ca5a0bf0c31211072c5425a89210
      https://github.com/OSGeo/grass/commit/4d4a007dd2c6ca5a0bf0c31211072c5425a89210
  Author: nilason <n_larsson at yahoo.com>
  Date:   2021-05-19 (Wed, 19 May 2021)

  Changed paths:
    M include/gis.h
    M lib/lidar/lidar.h
    M raster/r.param.scale/param.h
    M raster/r.surf.idw/main.h
    M raster3d/r3.showdspf/Ball.c
    M raster3d/r3.showdspf/togif.c
    M vector/v.hull/chull.c

  Log Message:
  -----------
  libgis: Enable the C99 bool type (#1567)

Enables globally the C99 'bool' type with its values 'true' and 'false'.

The old boolean constants 'TRUE' and 'FALSE' are still valid but
redefined to 'true' and 'false' to emphasize their equivalence.

(Re-)definitions of TRUE/FALSE in modules are removed.

This change was originally triggered by a conflict of v.hull -- defining
a local bool type -- with GDAL 3.3 which introduced the inclusion of
stdbool.h (#1563).