install.sh: Avoid find *

Although the local `etc` directory should contain only sane files, stick
to good habit and avoid `find *`, which misinterpretes filenames
starting with `-`. Also add quotes to avoid missinterpretation of
filenames with whitespace.

install.sh

@@ -104,12 +104,13 @@ function install_symlink()
 function install_etc_files()
 {
     while read -r path; do
+        path="${path#./}"
         if [[ -x etc/$path ]]; then
-            install_exec etc/$path "$DESTDIR$sysconfdir/$path"
+            install_exec "etc/$path" "$DESTDIR$sysconfdir/$path"
         else
-            install_data etc/$path "$DESTDIR$sysconfdir/$path"
+            install_data "etc/$path" "$DESTDIR$sysconfdir/$path"
         fi
-    done < <(cd etc ; find * -type f)
+    done < <(cd etc ; find ./* -type f)
 }
 
 function postinstall()