lock params from low level

[Antonio Linares]

#include <hbapiitm.h>

PHB_ITEM pBlock = NULL;

...

pBlock = hb_itemParam( 1 ); // 1 for first parameter. Automatically calls hb_gcGripGet()

...

hb_evalBlock0( pBlock );

...

hb_itemRelease( pBlock ); // automatically calls hb_gcGripDrop()