random: use proper return types on get_random_{int,long}_wait()

stable inclusion
from stable-v5.10.119
commit 33783ca3556e8d3965fe44aa79ae41ab19897189
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5L6BB

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=33783ca3556e8d3965fe44aa79ae41ab19897189



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commit 7c3a8a1d upstream.

Before these were returning signed values, but the API is intended to be
used with unsigned values.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Acked-by: Xie XiuQi <xiexiuqi@huawei.com>