!868 LoongArch: fix compile error caused by __ffs not defined

Merge Pull Request from: @Hongchen_Zhang 
 
after commit 0cba0556 ("cpumask: introduce for_each_cpu_or")
LoongArch code can not compile,the reason is __ffs is not found,
change the bitops.h include order to make it fine. 
 
Link:https://gitee.com/openeuler/kernel/pulls/868 

Reviewed-by: Guo Dongtai <guodongtai@kylinos.cn> 
Reviewed-by: Jialin Zhang <zhangjialin11@huawei.com> 
Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com> 

arch/loongarch/include/asm/bitops.h

@@ -13,7 +13,6 @@
 
 #include <asm/barrier.h>
 
-#include <asm-generic/bitops/find.h>
 #include <asm-generic/bitops/builtin-ffs.h>
 #include <asm-generic/bitops/builtin-fls.h>
 #include <asm-generic/bitops/builtin-__ffs.h>
@@ -21,6 +20,7 @@
 
 #include <asm-generic/bitops/ffz.h>
 #include <asm-generic/bitops/fls64.h>
+#include <asm-generic/bitops/find.h>
 
 #include <asm-generic/bitops/sched.h>
 #include <asm-generic/bitops/hweight.h>