MIPS: JZ4740: introduce CONFIG_MACH_INGENIC

In preparation for supporting Ingenic SoCs other than the JZ4740,
introduce MACH_INGENIC to Kconfig & move MACH_JZ4740 to a separate
entry selected by the board when appropriate. This allows MACH_INGENIC
to be used to enable things generic across Ingenic SoCs.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: Andrew Bresticker <abrestic@chromium.org>
Patchwork: https://patchwork.linux-mips.org/patch/10130/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 76efb02..006d814 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -289,9 +289,8 @@
 	 Members include the Acer PICA, MIPS Magnum 4000, MIPS Millennium and
 	 Olivetti M700-10 workstations.
 
-config MACH_JZ4740
-	bool "Ingenic JZ4740 based machines"
-	select SYS_HAS_CPU_MIPS32_R1
+config MACH_INGENIC
+	bool "Ingenic SoC based machines"
 	select SYS_SUPPORTS_32BIT_KERNEL
 	select SYS_SUPPORTS_LITTLE_ENDIAN
 	select SYS_SUPPORTS_ZBOOT_UART16550