cmd: qfw: remove qemu_fwcfg_free_files()

This patch is part of the qfw refactor work.

The qemu_fwcfg_free_files() function is only used in error handling in
ACPI table generation, let's not make this a core function and move it
to the right place.

Signed-off-by: Miao Yan <yanmiaobest@gmail.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/arch/x86/cpu/qemu/acpi_table.c b/arch/x86/cpu/qemu/acpi_table.c
index 49381ac..b17fa03 100644
--- a/arch/x86/cpu/qemu/acpi_table.c
+++ b/arch/x86/cpu/qemu/acpi_table.c
@@ -235,8 +235,17 @@
 	}
 
 out:
-	if (ret)
-		qemu_fwcfg_free_files();
+	if (ret) {
+		struct fw_cfg_file_iter iter;
+		for (file = qemu_fwcfg_file_iter_init(&iter);
+		     !qemu_fwcfg_file_iter_end(&iter);
+		     file = qemu_fwcfg_file_iter_next(&iter)) {
+			if (file->addr) {
+				free((void *)file->addr);
+				file->addr = 0;
+			}
+		}
+	}
 
 	free(table_loader);
 	return addr;