context: use the log.level from the config file

Use log.level from the config file if not otherwise set with
PIPEWIRE_DEBUG env.
Make client log.level = 0 by default to avoid spamming the console
with errors.

Fixes #725
Fixes #769

src/daemon/client-rt.conf.in

@@ -5,7 +5,7 @@ context.properties = {
     #mem.warn-mlock  = false
     #mem.allow-mlock = true
     #mem.mlock-all   = false
-    #log.level       = 2
+    log.level        = 0
 }
 
 context.spa-libs = {

src/daemon/client.conf.in

@@ -4,7 +4,7 @@ context.properties = {
     #mem.warn-mlock  = false
     #mem.allow-mlock = true
     #mem.mlock-all   = false
-    #log.level       = 2
+    log.level        = 0
 }
 
 context.spa-libs = {

src/daemon/jack.conf.in

@@ -5,7 +5,7 @@ context.properties = {
     #mem.warn-mlock  = false
     #mem.allow-mlock = true
     #mem.mlock-all   = false
-    #log.level       = 2
+    log.level        = 0
 }
 
 context.spa-libs = {

src/daemon/media-session.d/media-session.conf

@@ -4,6 +4,7 @@ context.properties = {
     # modules.
     #mem.mlock-all = false
     #support.dbus  = true
+    #log.level     = 2
 }
 
 context.spa-libs = {