tags: Fix spelling error in comment (is->if)

Signed-off-by: John Kacur <[e-mail]>
Signed-off-by: Michal Marek <[e-mail]>

scripts/tags.sh

···
           -name .git )                                   \
           -prune -o"
 
-# Do not use full path is we do not use O=.. builds
+# Do not use full path if we do not use O=.. builds
 if [ "${KBUILD_SRC}" = "" ]; then
 	tree=
 else