add cache parameter for 9p mount
add cache parameter for 9p mount

Signed-off-by: Wang Xu <0e9dfdf30d71e7ded2bba4a3dc006039c4b00f3d@gmail.com>

MarioCarrilloA/hyperstart,bergwolf/hyperstart,MarioCarrilloA/hyperstart,jefby/hyperstart,wcwxyz/hyperstart,hyperhq/hyperstart,gao-feng/hyperstart,gnawux/hyperstart,stigkj/hyperstart,MarioCarrilloA/hyperstart,gnawux/hyperstart,jefby/hyperstart,hyperhq/hyperstart,gnawux/hyperstart,bergwolf/hyperstart,stigkj/hyperstart,gao-feng/hyperstart,laijs/hyperstart,laijs/hyperstart,wcwxyz/hyperstart