arm: Disable ATAGs support

With the exceptions of ds109, ds414, icnova-a20-swac, nokia_rx51 and
stemmy, disable ATAG support.  A large number of platforms had enabled
support but never supported a kernel so old as to require it.  Further,
some platforms are old enough to support both, but are well supported by
devicetree booting, and have been for a number of years.  This is
because some of the ATAGs related functions have been re-used to provide
the same kind of information, but for devicetree or just generally to
inform the user.  When needed still, rename these functions to
get_board_revision() instead, to avoid conflicts.  In other cases, these
functions were simply unused, so drop them.

Cc: Andre Przywara <andre.przywara@arm.com>
Cc: Jagan Teki <jagan@amarulasolutions.com>
Cc: Phil Sutter <phil@nwl.cc>
Cc: Stefan Bosch <stefan_b@posteo.net>
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index d49f26f..dbf5ceb 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1907,6 +1907,36 @@
 	select SSCANF
 endchoice
 
+config SUPPORT_PASSING_ATAGS
+	bool "Support pre-devicetree ATAG-based booting"
+	depends on !ARM64
+	imply SETUP_MEMORY_TAGS
+	help
+	  Support for booting older Linux kernels, using ATAGs rather than
+	  passing a devicetree.  This is option is rarely used, and the
+	  semantics are defined at
+	  https://www.kernel.org/doc/Documentation/arm/Booting at section 4a.
+
+config SETUP_MEMORY_TAGS
+	bool "Pass memory size information via ATAG"
+	depends on SUPPORT_PASSING_ATAGS
+
+config CMDLINE_TAG
+	bool "Pass Linux kernel cmdline via ATAG"
+	depends on SUPPORT_PASSING_ATAGS
+
+config INITRD_TAG
+	bool "Pass initrd starting point and size via ATAG"
+	depends on SUPPORT_PASSING_ATAGS
+
+config REVISION_TAG
+	bool "Pass system revision via ATAG"
+	depends on SUPPORT_PASSING_ATAGS
+
+config SERIAL_TAG
+	bool "Pass system serial number via ATAG"
+	depends on SUPPORT_PASSING_ATAGS
+
 config ARCH_SUPPORT_TFABOOT
 	bool