update for mtk

Change-Id: If47846ba69383eca547ae05c5ee0371eb7395af4
do not release src when make release

Change-Id: I9ff647dd2acffa3100fa17a0f0581cc120c2e164
Update envsetup.sh

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Change-Id: I9c26bafd44f0b807e9981d5017d1d8439cb54158
Signed-off-by: mochangming <mochangming@xiaomi.com>
Amend envsetup.sh

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Change-Id: I92ef330756bab555f364d99f0a0ec5933cec40f0
Signed-off-by: mochangming <mochangming@xiaomi.com>
add s820 to makefile

Change-Id: If9c23311ade8840192f803ac9eccad7309708500