FreeBSD: Add missing OSS option --excl to man page.

While there, also improve the short description of this option in the
OSS backend part of usage help and jack_control.

freebsd/oss/JackOSSDriver.cpp

@@ -1288,7 +1288,7 @@ SERVER_EXPORT jack_driver_desc_t* driver_get_descriptor()
     jack_driver_descriptor_add_parameter(desc, &filler, "outchannels", 'o', JackDriverParamUInt, &value, NULL, "Playback channels", NULL);
 
     value.i = false;
-    jack_driver_descriptor_add_parameter(desc, &filler, "excl", 'e', JackDriverParamBool, &value, NULL, "Exclusif (O_EXCL) access mode", NULL);
+    jack_driver_descriptor_add_parameter(desc, &filler, "excl", 'e', JackDriverParamBool, &value, NULL, "Exclusive and direct device access", NULL);
 
     strcpy(value.str, OSS_DRIVER_DEF_DEV);
     jack_driver_descriptor_add_parameter(desc, &filler, "capture", 'C', JackDriverParamString, &value, NULL, "Input device", NULL);

man/jackd.0

@@ -582,6 +582,13 @@ Output device for playback.
 Whether or not to ignore hardware period size. 
 (default: false)
 
+.TP
+\fB\-e, \-\-excl \fIboolean\fR
+Request exclusive and direct access to the sound device.
+This avoids mixing and automatic audio conversion in the
+OSS driver, and the extra latency that comes with that.
+(default: false)
+
 .TP
 \fB\-I, \-\-input\-latency\fR
 Extra input latency (frames). 

solaris/oss/JackOSSDriver.cpp

@@ -759,7 +759,7 @@ SERVER_EXPORT jack_driver_desc_t* driver_get_descriptor()
     jack_driver_descriptor_add_parameter(desc, &filler, "outchannels", 'o', JackDriverParamUInt, &value, NULL, "Playback channels", NULL);
 
     value.i = false;
-    jack_driver_descriptor_add_parameter(desc, &filler, "excl", 'e', JackDriverParamBool, &value, NULL, "Exclusif (O_EXCL) access mode", NULL);
+    jack_driver_descriptor_add_parameter(desc, &filler, "excl", 'e', JackDriverParamBool, &value, NULL, "Exclusive and direct device access", NULL);
 
     strcpy(value.str, OSS_DRIVER_DEF_DEV);
     jack_driver_descriptor_add_parameter(desc, &filler, "capture", 'C', JackDriverParamString, &value, NULL, "Input device", NULL);