usbredir: improve license description

For consistency use 'libraries' and 'program' as component names and
adjust license string for readability when we conditionally specify
license for server program.

Signed-off-by: Rahul Bedarkar <rahul.bedarkar@imgtec.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/usbredir/usbredir.mk

@@ -7,14 +7,14 @@
 USBREDIR_VERSION = 0.7.1
 USBREDIR_SOURCE = usbredir-$(USBREDIR_VERSION).tar.bz2
 USBREDIR_SITE = http://spice-space.org/download/usbredir
-USBREDIR_LICENSE = LGPLv2.1+
+USBREDIR_LICENSE = LGPLv2.1+ (libraries)
 USBREDIR_LICENSE_FILES = COPYING.LIB
 USBREDIR_INSTALL_STAGING = YES
 USBREDIR_DEPENDENCIES = host-pkgconf libusb
 
 ifeq ($(BR2_PACKAGE_USBREDIR_SERVER),y)
 
-USBREDIR_LICENSE += (for the library), GPLv2+ (for the server)
+USBREDIR_LICENSE := $(USBREDIR_LICENSE), GPLv2+ (program)
 USBREDIR_LICENSE_FILES += COPYING
 
 else # BR2_PACKAGE_USBREDIR_SERVER != y