treewide: strip trailing whitespace

treewide: strip trailing whitespace

Strip trailing whitespace in all code:
find . -type f | grep "\.c$" | xargs sed -i 's/[ \t]\+$//'
find . -type f | grep "\.h$" | xargs sed -i 's/[ \t]\+$//'
find . -type f | grep "\.dts$" | xargs sed -i 's/[ \t]\+$//'
find . -type f | grep "\.dtsi$" | xargs sed -i 's/[ \t]\+$//'

Signed-off-by: Mieczyslaw Nalewaj <namiltd@yahoo.com>
Link: https://github.com/openwrt/openwrt/pull/22840
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>