Docs: Remove outdated paragraph about installing a solver being required for SMTChecker pragmas

Author: cameel

docs/layout-of-source-files.rst

@@ -153,15 +153,6 @@ since Solidity 0.7.4.
 SMTChecker
 ~~~~~~~~~~
 
-This component has to be enabled when the Solidity compiler is built
-and therefore it is not available in all Solidity binaries.
-The :ref:`build instructions<smt_solvers_build>` explain how to activate this option.
-It is activated for the Ubuntu PPA releases in most versions,
-but not for the Docker images, Windows binaries or the
-statically-built Linux binaries. It can be activated for solc-js via the
-`smtCallback <https://github.com/argotorg/solc-js#example-usage-with-smtsolver-callback>`_ if you have an SMT solver
-installed locally and run solc-js via node (not via the browser).
-
 If you use ``pragma experimental SMTChecker;``, then you get additional
 :ref:`safety warnings<formal_verification>` which are obtained by querying an
 SMT solver.