arm32: kaslr: pop visibility when compile decompress boot code as we need relocate BSS by GOT.

hulk inclusion
commit 6337511516862e5a4d2d5a96481510e4a7a12b1b
category: feature
feature: ARM kaslr support
bugzilla: 47952
CVE: NA

-------------------------------------------------

If we not hide the GOT, when insert module which reference global
variable we got error "Unknown symbol_GLOBAL_OFFSET_TABLE_ (err 0)".
Signed-off-by: NYe Bin <yebin10@huawei.com>
Reviewed-by: NJing Xiangfeng <jingxiangfeng@huawei.com>
Signed-off-by: Nzhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: NCui GaoSheng <cuigaosheng1@huawei.com>
Reviewed-by: NXiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

arch/arm/boot/compressed/decompress.c

 // SPDX-License-Identifier: GPL-2.0
 #define _LINUX_STRING_H_
 
+#ifdef CONFIG_RANDOMIZE_BASE
+#pragma GCC visibility pop
+#endif
+
 #include <linux/compiler.h>	/* for inline */
 #include <linux/types.h>	/* for size_t */
 #include <linux/stddef.h>	/* for NULL */

arch/arm/boot/compressed/misc.c

@@ -16,6 +16,9 @@
  *  which should point to addresses in RAM and cleared to 0 on start.
  *  This allows for a much quicker boot time.
  */
+#ifdef CONFIG_RANDOMIZE_BASE
+#pragma GCC visibility pop
+#endif
 
 unsigned int __machine_arch_type;