Docs: Extend CPL limit in coding rules

Signed-off-by: Anton Komlev <anton.komlev@arm.com>
Change-Id: If6d9507773eca9b2e5f40bb9f614a7154c421f62
diff --git a/docs/contributing/coding_guide.rst b/docs/contributing/coding_guide.rst
index 5b75d36..3a59a41 100644
--- a/docs/contributing/coding_guide.rst
+++ b/docs/contributing/coding_guide.rst
@@ -47,7 +47,7 @@
 - Use void argument if your function doesn't contain any argument.
 - Use C90 ``/* */`` for comments rather than C99 ``//``
 - No trailing spaces in code.
-- Max 80 characters length. Text files are exception as stated above.
+- Keep up to 100 characters per line but 140 chars can be accepted exceptionally.
 - Open curly brace ``{`` at the same if/else/while/for/switch statement line.
 - Use curly braces ``{ }`` for one line statement bodies also.
 - Put open curly brace in the line below the function header.
@@ -76,4 +76,4 @@
 
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-*Copyright (c) 2018-2021, Arm Limited. All rights reserved.*
+*Copyright (c) 2018-2022, Arm Limited. All rights reserved.*