Linux default Makefile target restored to /usr/local

git-svn-id: http://subversion.jackaudio.org/jack/jack2/trunk/jackmp@1734 0c269be4-1314-0410-8aa9-9f06e86f4224

linux/Makefile

@@ -1,7 +1,7 @@
 # Type "make" or "make all" to compile ALSA driver, and "make freebob" to compile FREEBOB driver.
 
 # Choose the installation location
-prefix := /usr
+prefix := /usr/local
 prefix := ${DESTDIR}${prefix}
 libdir := lib