DXF: Don't use OCS for the insertion point of MTEXT

[Alan Thomas]

The DXF specification is vague on this point, but from experimentation with AutoCAD, the insertion point of MTEXT is in the global coordinate system, not the OCS.

See the attached DXF for differences between TEXT and MTEXT on this front. The correct display of this DXF is with 5 of the 6 objects (all except "TEXT extrusion 0.2,0.4,0.894427191, no 11/21/31") shown close to each other at 320000 metres east. However, OGR incorrectly positions one of the MTEXT objects elsewhere:

OGRFeature(entities):5
  OGR_GEOMETRY (String) = POINT
  Layer (String) = 0
  SubClasses (String) = AcDbEntity:AcDbMText
  ExtendedEntity (String) = ACAD_MTEXT_COLUMN_INFO_BEGIN     75      2     79      0     76      1     78      0     48 60.0     49 1.0     50      1 0.0 ACAD_MTEXT_COLUMN_INFO_END
  EntityHandle (String) = 622
  Text (String) = MTEXT extrusion 0.2,0.4,0.894427191
  Style = LABEL(f:"Arial",t:"MTEXT extrusion 0.2,0.4,0.894427191",s:1g,p:7,c:#000000)
  POINT Z (-2612219.70112002 -4508897.6494401 2600550.41193403)

The insertion point of TEXT *is* in the OCS, so the positioning of the TEXT objects in the file is correct.

Patch would be to remove ​this line.

[Even Rouault]

In 40171:

DXF: do not apply the OCS transformation for MTEXT (patch by atlight, fixes #7049)