doc: sandbox: Correct the memory size config option
It should be CONFIG_SANDBOX_RAM_SIZE_MB.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
diff --git a/doc/arch/sandbox.rst b/doc/arch/sandbox.rst
index bc670b9..246ab5b 100644
--- a/doc/arch/sandbox.rst
+++ b/doc/arch/sandbox.rst
@@ -143,7 +143,7 @@
Memory Emulation
----------------
-Memory emulation is supported, with the size set by CONFIG_SYS_SDRAM_SIZE.
+Memory emulation is supported, with the size set by CONFIG_SANDBOX_RAM_SIZE_MB.
The -m option can be used to read memory from a file on start-up and write
it when shutting down. This allows preserving of memory contents across
test runs. You can tell U-Boot to remove the memory file after it is read