imagemagick: do not install magick-baseconfig.h repeatedly

Both targets install-data-local & install-includeHEADERS will install
header file magick-baseconfig.h to the same location, and they might
be run in the same time while enabling parallel build:

* target dependencies:
  + install-data-am: ... install-data-local ... install-includeHEADERS

* make install error:
  /usr/bin/install: cannot create regular file \
  `.../usr/include/ImageMagick-6/magick/magick-baseconfig.h': \
  File exists \
  make[3]: *** [install-magickincarchHEADERS] Error 1

* reproduce the error:
  $ /usr/bin/install test /tmp & /usr/bin/install test /tmp
  [1] 4052
  /usr/bin/install: cannot create regular file `/tmp/test': File exists
  [1]+  Exit 1                  /usr/bin/install test /tmp

Just disable the one from install-data-local to remove this race issue.

Signed-off-by: Wenzong Fan <wenzong.fan@windriver.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>