sandbox: efi_loader: Correct use of addresses as pointers

The cache-flush function is incorrect which causes a crash in the
remoteproc tests with arm64.

Fix both problems by using map_sysmem() to convert an address to a
pointer and map_to_sysmem() to convert a pointer to an address.

Also update the image-loader's cache-flushing logic.

Signed-off-by: Simon Glass <sjg@chromium.org>
Fixes: 3286d223fd ("sandbox: implement invalidate_icache_all()")
Acked-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

Changes in v6:
- Re-introduce

Changes in v2:
- Drop message about EFI_LOADER

arch/sandbox/cpu/cache.c              |  8 +++++++-
 drivers/remoteproc/rproc-elf-loader.c | 18 +++++++++++-------
 lib/efi_loader/efi_image_loader.c     |  3 ++-
 3 files changed, 20 insertions(+), 9 deletions(-)

Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

lib/efi_loader/efi_image_loader.c

@@ -13,6 +13,7 @@
 #include <efi_loader.h>
 #include <log.h>
 #include <malloc.h>
+#include <mapmem.h>
 #include <pe.h>
 #include <sort.h>
 #include <crypto/mscode.h>
@@ -977,7 +978,7 @@ efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle,
 	}
 
 	/* Flush cache */
-	flush_cache((ulong)efi_reloc,
+	flush_cache(map_to_sysmem(efi_reloc),
 		    ALIGN(virt_size, EFI_CACHELINE_SIZE));
 
 	/*