~/.config/dwm: Support muting/unmuting audio

.config/dwm/config.h

@@ -66,6 +66,7 @@ static const char *termcmd[]  = { "/usr/bin/sakura", NULL };
static const char *volumedowncmd[] = { "amixer", "set", "Master", "5%-", NULL };
static const char *volumeupcmd[] = { "amixer", "set", "Master", "5%+", NULL };
static const char *volumetogglecmd[] = { "amixer", "set", "Master", "toggle", NULL };
static const char *screenlockcmd[] = { "slock", NULL };
@@ -107,6 +108,7 @@ static Key keys[] = {
	{ 0,                            XF86XK_AudioLowerVolume, spawn, { .v = volumedowncmd } },
	{ 0,                            XF86XK_AudioRaiseVolume, spawn, { .v = volumeupcmd } },
	{ 0,                            XF86XK_AudioMute       , spawn, { .v = volumetogglecmd } },
	{ MODKEY|ShiftMask,             XK_l,      spawn,          { .v = screenlockcmd } },
};