target/loongarch: Avoid bits shift exceeding width of bool type

target/loongarch: Avoid bits shift exceeding width of bool type

Variable env->cf[i] is defined as bool type, it is treated as int type
with shift operation. However the max possible width is 56 for the shift
operation, exceeding the width of int type. And there is existing api
read_fcc() which is converted to u64 type with bitwise shift, it can be
used to dump fp registers into coredump note segment.

Resolves: Coverity CID 1561133
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240914064645.2099169-1-maobibo@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>