如何使用bitbake设置/etc/timestamp？

SUMMARY = "My Application"
LICENSE = "MIT"
LIC_FILES_CHKSUM = "file://LICENSE;md5=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"

SRC_URI = "git://example.com/myapp.git"

S = "${WORKDIR}/git"

do_compile() {
    # 编译代码的命令
    bitbakeutils_do_something
}

do_install() {
    # 安装代码的命令
    bitbakeutils_do_something_else
    install -d ${D}/etc
    install -m 0644 ${WORKDIR}/timestamp ${D}/etc/timestamp
}

FILES_${PN} += "/etc/timestamp"

$ bitbake myapp