Experimental VGICD and VIRQ Forwarding integration in test_vdev_sample.c. Guest configures sp804, it's irq and irq handler while hyp does not touch anything about sp804.\n BUGFIX: hyp saves guest's lr register that's shared with hyp mode
[v1-virq] Moved callback handler for vgicd_changed_istatus

Location of the callback handler is changed from tests_vdev.c to virqmap.c
Location of the callback registration is changed from tests.c to virqmap.c
Merge pull request #62 from Wonseok/v1-virq

Added callback handler for vgicd_changed_istatus in virqmap.c
context: saves sctlr and sp_usr for better linux guest compatibility (enables running bmguest at guest 1 along side linux at guest 0). bmguest uart and sp804 base addresses are fixed at 0x1C090000 and 0x1C110000