mpkg: fix shellcheck issue
mpkg: fix shellcheck issue

The following commit has introduced a shell check issue.

	10e4382 mpkg: add upgrade function

It reports the following error.

	In bin/mpkg line 843:
		for pkg in $*; do
	                   ^-- SC2048: Use "$@" (with quotes) to prevent whitespace problems.

gazoo74/mpkg,gazoo74/mpkg