[app][uefi] Pass DTB to linux kernel

platform/include/platform.h

@@ -82,5 +82,8 @@ void platform_init(void);
 /* called by the arch init code to get the platform to set up any mmu mappings it may need */
 void platform_init_mmu_mappings(void);
 
+/* Called by LK to get the device tree */
+const void *get_fdt(void);
+
 __END_CDECLS
 

platform/init.c

@@ -27,3 +27,8 @@ __WEAK void platform_init(void) {
 __WEAK void platform_quiesce(void) {
 }
 
+
+__WEAK const void *get_fdt(void) {
+    return NULL;
+}
+

platform/qemu-virt-arm/platform.c

@@ -60,6 +60,10 @@ struct mmu_initial_mapping mmu_initial_mappings[] = {
 
 const void *fdt = (void *)KERNEL_BASE;
 
+const void *get_fdt(void) {
+    return fdt;
+}
+
 void platform_early_init(void) {
     const struct pl011_config uart_config = {
         .base = UART_BASE,