um: vector: Fix indentation for help message

For consistency with other help messages, use four spaces for
indentation instead of a tab plus a space.

Signed-off-by: Tiwei Bie <[e-mail]>
Signed-off-by: Johannes Berg <[e-mail]>

arch/um/drivers/vector_kern.c

···
 __setup("vec", vector_setup);
 __uml_help(vector_setup,
 "vec[0-9]+:<option>=<value>,<option>=<value>\n"
-"	 Configure a vector io network device.\n\n"
+"    Configure a vector io network device.\n\n"
 );
 
 late_initcall(vector_init);