mb/emulation/*-riscv: Initialize cbmem in romstage

It is expected that cbmem is initialized in romstage. The qemu-riscv
target did not perform that correctly. Fix this omission.

Change-Id: I00f8e3b315e57a5c042889f48450f79d263f24b1
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/36446
Reviewed-by: Philipp Hug <philipp@hug.cx>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/emulation/qemu-riscv/romstage.c

@@ -13,11 +13,13 @@
  * GNU General Public License for more details.
  */
 
+#include <cbmem.h>
 #include <console/console.h>
 #include <program_loading.h>
 
 void main(void)
 {
 	console_init();
+	cbmem_initialize_empty();
 	run_ramstage();
 }

src/mainboard/emulation/spike-riscv/romstage.c

@@ -13,6 +13,7 @@
  * GNU General Public License for more details.
  */
 
+#include <cbmem.h>
 #include <console/console.h>
 #include <program_loading.h>
 
@@ -20,6 +21,8 @@ void main(void)
 {
 	console_init();
 
+	cbmem_initialize_empty();
+
 	//query_mem(configstring(), &base, &size);
 	//printk(BIOS_SPEW, "0x%zx bytes of memory at 0x%llx\n", size, base);