python 2.7.4: disable leftover --with-dtrace logic

Disable the --with-dtrace logic left in the formula after `option 'with-dtrace'` was commented out. 

A recent commit (https://github.com/mxcl/homebrew/commit/fbf7be913a7693c05a4fa40050b7819781b26df0) disabled
the "option 'with-dtrace'" line because it wasn't working with 2.7.4.
But the with-dtrace logic in the patches and configure sections was still
active, so if you specified it on the command line, or were doing an upgrade
of an earlier build that used --with-dtrace, it'd still try to apply the
old patch, and break the build. This comments it out.

Fixes #19377.