Making the CHUNKSIZE setable via environment variable
Making the CHUNKSIZE setable via environment variable

With this modification the CHUNKSIZE is setable by QV4_MM_MAX_CHUNK_SIZE
environment variable so the memory usage which is important for embedded
devices can be finetuned.

Change-Id: I3cd75158f2255651edd341873de035c1222e3c92
Reviewed-by: Lars Knoll <a812617a4072dcbeb80684eca0f369f0083af109@digia.com>

mgrunditz/qtdeclarative-2d,mgrunditz/qtdeclarative-2d,qmlc/qtdeclarative,qmlc/qtdeclarative,qmlc/qtdeclarative,mgrunditz/qtdeclarative-2d,mgrunditz/qtdeclarative-2d,qmlc/qtdeclarative,qmlc/qtdeclarative,mgrunditz/qtdeclarative-2d,mgrunditz/qtdeclarative-2d,qmlc/qtdeclarative,qmlc/qtdeclarative,mgrunditz/qtdeclarative-2d,qmlc/qtdeclarative