ChangeLog:
* libsframe/doc/sframe-spec.texi
@multitable {Bit offset} {@code{isroot}} {Length of variable-length data for this type (some kinds only).}
@headitem Bit offset @tab Name @tab Description
-@item 7--5
+@item 7--6
@tab @code{unused}
@tab Unused bits.
+@item 5
+@tab @code{pauth_key}
+@tab Specify which key is used for signing the return addresses in the SFrame
+FDE. Two possible values: SFRAME_AARCH64_PAUTH_KEY_A (0) or
+SFRAME_AARCH64_PAUTH_KEY_B (1).
+
@item 4
@tab @code{fdetype}
@tab SFRAME_FDE_TYPE_PCMASK (1) or SFRAME_FDE_TYPE_PCINC (0). @xref{The SFrame FDE types}.