x86: Add an __end symbol to signal the end of the U-Boot binary

With this symbol we can easy append something (e.g. an FDT) to the U-Boot
binary and access it from within U-Boot.

Signed-off-by: Simon Glass <sjg@chromium.org>

arch/x86/cpu/u-boot.lds

@@ -67,6 +67,8 @@ SECTIONS
 	__rel_dyn_start = .;
 	.rel.dyn : { *(.rel.dyn) }
 	__rel_dyn_end = .;
+	. = ALIGN(4);
+	_end = .;
 
 	/DISCARD/ : { *(.dynstr*) }
 	/DISCARD/ : { *(.dynamic*) }

arch/x86/include/asm/u-boot-x86.h

@@ -31,6 +31,7 @@ extern ulong __rel_dyn_start;
 extern ulong __rel_dyn_end;
 extern ulong __bss_start;
 extern ulong __bss_end;
+extern ulong _end;
 
 /* cpu/.../cpu.c */
 int x86_cpu_init_r(void);

arch/x86/lib/init_helpers.c

@@ -188,7 +188,7 @@ int find_fdt(void)
 	gd->fdt_blob = _binary_dt_dtb_start;
 #elif defined CONFIG_OF_SEPARATE
 	/* FDT is at end of image */
-	gd->fdt_blob = (void *)(_end_ofs + _TEXT_BASE);
+	gd->fdt_blob = (ulong *)&_end;
 #endif
 	/* Allow the early environment to override the fdt address */
 	gd->fdt_blob = (void *)getenv_ulong("fdtcontroladdr", 16,