mount: rename "quiet" to "silent" (MS_SILENT)

The quiet mount option was in collision with vfat and hfs mount
options. The option was also undocumented -- so it's probably safe to
rename the option than add some ugly hacks or exceptions for vfat/hfs
to the mount(8) code.

Reported-by: https://bugzilla.redhat.com/show_bug.cgi?id=622089
Signed-off-by: Karel Zak <kzak@redhat.com>

mount/mount.8

@@ -963,6 +963,12 @@ Do not allow set-user-identifier or set-group-identifier bits to take
 effect. (This seems safe, but is in fact rather unsafe if you have
 suidperl(1) installed.)
 .TP
+.B silent
+Turn on the silent flag.
+.TP
+.B loud
+Turn off the silent flag.
+.TP
 .B owner
 Allow an ordinary (i.e., non-root) user to mount the filesystem if he
 is the owner of the device.

mount/mount.c

@@ -172,7 +172,7 @@ static const struct opt_map opt_map[] = {
   { "nosub",	0, 0, MS_NOSUB	},	/* don't allow submounts */
 #endif
 #ifdef MS_SILENT
-  { "quiet",	0, 0, MS_SILENT    },	/* be quiet  */
+  { "silent",	0, 0, MS_SILENT    },	/* be quiet  */
   { "loud",	0, 1, MS_SILENT    },	/* print out messages. */
 #endif
 #ifdef MS_MANDLOCK

mount/mount_constants.h

@@ -37,8 +37,8 @@
 #ifndef MS_REC
 #define MS_REC		0x4000	/* 16384: Recursive loopback */
 #endif
-#ifndef MS_VERBOSE
-#define MS_VERBOSE	0x8000	/* 32768 */
+#ifndef MS_SILENT
+#define MS_SILENT	0x8000	/* 32768 (was MS_VERBOSE) */
 #endif
 #ifndef MS_RELATIME
 #define MS_RELATIME	0x200000 /* 200000: Update access times relative