powerpc/mm/hash64: Don't test for machine type to detect HEA special case

Instead, check for FW_FEATURE_SPLPAR. This should be roughtly equivalent
as all pseries machiens that can have an HEA also support SPLPAR and
no other machine type does.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/mm/hash_utils_64.c

@@ -527,7 +527,8 @@ static bool might_have_hea(void)
 	 * we will never see an HEA ethernet device.
 	 */
 #ifdef CONFIG_IBMEBUS
-	return !cpu_has_feature(CPU_FTR_ARCH_207S);
+	return !cpu_has_feature(CPU_FTR_ARCH_207S) &&
+		!firmware_has_feature(FW_FEATURE_SPLPAR);
 #else
 	return false;
 #endif
@@ -593,7 +594,7 @@ static void __init htab_init_page_sizes(void)
 			 * would stop us accessing the HEA ethernet. So if we
 			 * have the chance of ever seeing one, stay at 4k.
 			 */
-			if (!might_have_hea() || !machine_is(pseries))
+			if (!might_have_hea())
 				mmu_io_psize = MMU_PAGE_64K;
 		} else
 			mmu_ci_restrictions = 1;