ARM: ux500: reform Ux500 family names

Counting the U9540 and the new U8540 as a U8500 family member
does not work. Instead, split the function in two:

cpu_is_u8500_family() covering U8500 and U8520
cpu_is_ux540_family() covering U9540 and U8540

This works much better in practice. Update users to keep the
same behaviour.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/arch/arm/mach-ux500/cpu.c b/arch/arm/mach-ux500/cpu.c
index e2360e7..4b0a9b3 100644
--- a/arch/arm/mach-ux500/cpu.c
+++ b/arch/arm/mach-ux500/cpu.c
@@ -51,7 +51,7 @@
 	void __iomem *dist_base;
 	void __iomem *cpu_base;
 
-	if (cpu_is_u8500_family()) {
+	if (cpu_is_u8500_family() || cpu_is_ux540_family()) {
 		dist_base = __io_address(U8500_GIC_DIST_BASE);
 		cpu_base = __io_address(U8500_GIC_CPU_BASE);
 	} else