docs: fix ff-a manifest binding document

The support for runtime-model has never been implemented by any SPMC.
Hence, remove the corresponding field from binding document.

Also, fix the incorrect description of the `managed-exit-virq` property.

Signed-off-by: Madhukar Pappireddy <madhukar.pappireddy@arm.com>
Change-Id: I0a5ef3f08202a8c76edd9a6e1ac680ac3a38ca60
diff --git a/docs/components/ffa-manifest-binding.rst b/docs/components/ffa-manifest-binding.rst
index c5dad14..2b6382b 100644
--- a/docs/components/ffa-manifest-binding.rst
+++ b/docs/components/ffa-manifest-binding.rst
@@ -122,7 +122,7 @@
 - managed-exit-virq
    - value type: <empty>
    - Indicates if the partition needs managed exit, if supported, to be signaled
-     through vFIQ signal.
+     through vIRQ signal.
 
 - ns-interrupts-action [mandatory]
    - value type: <u32>
@@ -143,12 +143,6 @@
       - 0x0: Other-Secure interrupt is queued
       - 0x1: Other-Secure interrupt is signaled
 
-- runtime-model
-   - value type: <u32>
-   - Indicates whether the SP execution can be preempted.
-   - This field is deprecated in favor of other-s-interrupts-action and
-     ns-interrupts-action fields in the FF-A v1.1 spec.
-
 - has-primary-scheduler
    - value type: <empty>
    - Presence of this field indicates that the partition implements the primary