!250 add UPROBE_ALTER_PC flag for uprobe mechanism

Merge Pull Request from: @anatas 
 
[Description]
We try to implement a live-patch mechanism in the userspace based on the UPROBE.
In the handler, we may change the PC register.
In this case, UPROBE must skip the handle of the next instruction.

[Testing]
kernel options:
UPROBES_SUPPORT_PC_ALTER=y

 
 
Link:https://gitee.com/openeuler/kernel/pulls/250

 
Reviewed-by: Xu Kuohai <xukuohai@huawei.com>
Reviewed-by: Liu Chao <liuchao173@huawei.com>
Reviewed-by: Zheng Zengkai <zhengzengkai@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>