scripts/coccinelle: drop bugon.cocci

The BUG_ON script was never safe, in that it was not able to check
whether the condition was side-effecting.  At this point, BUG_ON
should be well known, so it has probably outlived its usefuless.
Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Suggested-by: Matthew Wilcox <willy@infradead.org>

scripts/coccinelle/misc/bugon.cocci

-// SPDX-License-Identifier: GPL-2.0-only
-/// Use BUG_ON instead of a if condition followed by BUG.
-///
-//# This makes an effort to find cases where BUG() follows an if
-//# condition on an expression and replaces the if condition and BUG()
-//# with a BUG_ON having the conditional expression of the if statement
-//# as argument.
-//
-// Confidence: High
-// Copyright: (C) 2014 Himangi Saraogi.
-// Comments:
-// Options: --no-includes --include-headers
-
-virtual patch
-virtual context
-virtual org
-virtual report
-
-//----------------------------------------------------------
-//  For context mode
-//----------------------------------------------------------
-
-@depends on context@
-expression e;
-@@
-
-*if (e) BUG();
-
-//----------------------------------------------------------
-//  For patch mode
-//----------------------------------------------------------
-
-@depends on patch@
-expression e;
-@@
-
--if (e) BUG();
-+BUG_ON(e);
-
-//----------------------------------------------------------
-//  For org and report mode
-//----------------------------------------------------------
-
-@r depends on (org || report)@
-expression e;
-position p;
-@@
-
- if (e) BUG@p ();
-
-@script:python depends on org@
-p << r.p;
-@@
-
-coccilib.org.print_todo(p[0], "WARNING use BUG_ON")
-
-@script:python depends on report@
-p << r.p;
-@@
-
-msg="WARNING: Use BUG_ON instead of if condition followed by BUG.\nPlease make sure the condition has no side effects (see conditional BUG_ON definition in include/asm-generic/bug.h)"
-coccilib.report.print_report(p[0], msg)
-