Use B instead of Zba/Zbb/Zbs in RVA22U64

src/profiles.adoc

@@ -723,6 +723,13 @@ instructions in the mandatory A extension.
 
 The following mandatory extensions are new for RVA22U64.
 
+- *B* Bit-manipulation instructions.
+
+NOTE: The B extension comprises the Zba, Zbb, and Zbs extensions.
+At the time of RVA22U64's ratification, the B extension had not yet been
+defined, and so RVA22U64 explicitly mandated Zba, Zbb, and Zbs instead.
+Mandating B is equivalent.
+
 - *Zihpm* Hardware performance counters.
 
 NOTE: Zihpm was optional in RVA20U64.
@@ -736,10 +743,6 @@ should use the instruction whenever it would make sense and that
 implementors are expected to exploit this information to optimize
 hardware execution.
 
-- *Zba* Address computation.
-- *Zbb* Basic bit manipulation.
-- *Zbs* Single-bit instructions.
-
 - *Zic64b* Cache blocks must be 64 bytes in size, naturally aligned in the
 address space.