COMP: Revert tcl precision to default value

Some time ago, the tcl_precision was set to 6 digits. This patch
removes the explicit setting of tcl_precision so that applications
will see the default precision (12 digits) unless the application
changes it explicitly.

Change-Id: I852d2f996efd08e8a3548272a6739d834d14165c
Merge topic 'TclPrecision' into master

992028b0 COMP: Revert tcl precision to default value