powerpc/pseries: Fix vector5 in ibm architecture vector table

With ibm,dynamic-memory-v2 and ibm,drc-info coming around the same
time, byte22 in vector5 of ibm architecture vector table got set twice
separately. The end result is that guest kernel isn't advertising
support for ibm,dynamic-memory-v2.

Fix this by removing the duplicate assignment of byte22.

Fixes: 02ef6dd8 ("powerpc: Enable support for ibm,drc-info devtree property")
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/kernel/prom_init.c

@@ -874,7 +874,6 @@ struct ibm_arch_vec __cacheline_aligned ibm_architecture_vec = {
 		.mmu = 0,
 		.hash_ext = 0,
 		.radix_ext = 0,
-		.byte22 = 0,
 	},
 
 	/* option vector 6: IBM PAPR hints */