editorconfig: don't trim trailing whitespaces in runtime/doc

closes: #16058

Signed-off-by: Luca Saccarola <github.e41mv@aleeas.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/.editorconfig b/.editorconfig
index bda9fd2..a586af4 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -19,3 +19,7 @@
 # Markdown uses trailing whitespaces to do an hard line break
 # https://spec.commonmark.org/0.31.2/#hard-line-breaks
 trim_trailing_whitespace = false
+
+[runtime/doc/**.txt]
+# It can mess up some documentation by trying to strip trailing whitespaces
+trim_trailing_whitespace = false