fix[cmake]: fix static build

Signed-off-by: MarcA711 <40744649+MarcA711@users.noreply.github.com>
Signed-off-by: Herman Chen <herman.chen@rock-chips.com>
Change-Id: I4bd4a7543584685b20089d3953e700f5612523e7

merge_static_lib.sh

@@ -0,0 +1,10 @@
+#!/bin/bash
+
+cd $1
+rm -rf mpp/lib'$2$'.a
+
+SCRIPT=$'CREATE mpp/lib'$2$'.a\n'
+SCRIPT=$SCRIPT$(find . -name '*.a' -exec echo 'ADDLIB {}' \;)
+SCRIPT=$SCRIPT$'\nSAVE\nEND\n'
+
+ar -M <<< $SCRIPT