package/pseudo: force rpath and pass our host CFLAGS

package/pseudo: force rpath and pass our host CFLAGS

pseudo whines when those are not set, and tries to find a suitable
value; this is usually correct but risk an incorrect guess in corner
cases.

Rather than leaving those in guess-mode, just force them to values we
know are correct.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Gaël PORTAY <gael.portay@savoirfairelinux.com>
Cc: Patrick Keroulas <patrick.keroulas@savoirfairelinux.com>
Cc: Erico Nunes <nunes.erico@gmail.com>
Cc: Julien BOIBESSOT <julien.boibessot@free.fr>
Cc: Arnout Vandecappelle <arnout@mind.be>
Reviewed-by: Arnout Vandecappelle <arnout@mind.be>
[Thomas: use double quotes instead of single quotes.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>