arm64: dts: renesas: ironhide: Describe inline ECC carveouts

arm64: dts: renesas: ironhide: Describe inline ECC carveouts

The DBSC5 DRAM controller protects DRAM content using inline ECC.
The inline ECC utilizes areas of DRAM for its operation, which are
in the DRAM address range, but must not be accessed or modified.
Describe the inline ECC carveout areas used by the DBSC5 controller
on this hardware as reserved-memory, which must not be accessed.
Include DRAM areas which are unprotected by ECC as well, those are
parts of the DRAM which directly precede the ECC carveout.

In case of high DRAM utilization, unless the inline ECC carveouts
are properly reserved, Linux may use and corrupt the memory used
by the DBSC5 DRAM controller for inline ECC, which would lead to
the system becoming unstable.

Fixes: ad142a4ef710 ("arm64: dts: renesas: r8a78000: Add initial Ironhide board support")
Cc: stable@vger.kernel.org
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260710160450.64967-1-marek.vasut+renesas@mailbox.org
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>