pgsql: Fix breakage in GEODEBUG debug code.

Fix breakage in GEODEBUG debug code.

LINE doesn't have an "m" field (anymore anyway).  Also fix unportable
assumption that %x can print the result of pointer subtraction.

In passing, improve single_decode() in minor ways:
* Remove unnecessary leading-whitespace skip (strtod does that already).
* Make GEODEBUG message more intelligible.
* Remove entirely-useless test to see if strtod returned a silly pointer.
* Don't bother computing trailing-whitespace skip unless caller wants
  an ending pointer.

This has been broken since 261c7d4b653bc3e44c31fd456d94f292caa50d8f.
Although it's only debug code, might as well fix the 9.4 branch too.

Branch
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REL9_4_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/900679245de9d7f407dc72c34a5beb4124955f6f

Modified Files
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src/backend/utils/adt/geo_ops.c |   26 +++++++++++++-------------
1 file changed, 13 insertions(+), 13 deletions(-)