sw64: generate call instruction with disp 0

Sunway inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I645S9



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The disp is jump hint and target is PC+4*SEXT(disp[15:0]).

Signed-off-by: He Sheng <hesheng@wxiat.com>
Reviewed-by: Cui Wei <cuiwei@wxiat.com>
Signed-off-by: Gu Zitao <guzitao@wxiat.com>