qemu: Improve and add PACKAGECONFIG options

qemu: Improve and add PACKAGECONFIG options

Move the '--disable-bluez' and '--disable-iscsi' options to
PACKAGECONFIG. And added the ${BLUEZ} dependency.

Fix up the 'gcrypt' option to depend on 'libgcrypt' instead of gcrypt.
This is the expected dependency as noted in the QEMU configure help.

Handle the '--audio-drv-list' option inside the PACKAGECONFIG[alsa]
args. The previous setting uses a ',' to denote the options for the arg
however a space inside quotes is also acceptable and allows the arg to
be used into the PACKAGECONFIG flag.

(From OE-Core rev: 0aca9b735c6f9d7ffe2826e624942a563c501d1f)

Signed-off-by: Nathan Rossi <nathan@nathanrossi.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>