New device: Sony Xperia M4 Aqua (sony-tulip)

Hi guys, here I am again with an another port for Sony device, this time for Xperia M4. I haven't got display to work yet, and it's hard for me to test things since my friend that tests it for me lives faaar away (my device is dead, press F to pay respect).

I documented what works and what doesn't on the wiki https://wiki.postmarketos.org/wiki/Sony_Xperia_M4_Aqua_(sony-tulip).

Should be noted that this device is a pretty nice candidate for mainline kernel since it runs 4.x kernels to some extend and its soc (8939/8936, that's a long story) is from 8916 family

Also, when making the PR I just realised I broke guidelines by merging master, but my git knowledge is not very good and I don't want to break anything

device/device-sony-tulip/APKBUILD

+# Reference: <https://postmarketos.org/devicepkg>
+pkgname="device-sony-tulip"
+pkgdesc="Sony Xperia M4 Aqua"
+pkgver=0.1
+pkgrel=0
+url="https://postmarketos.org"
+license="MIT"
+arch="aarch64"
+options="!check !archcheck"
+depends="postmarketos-base linux-sony-tulip mkbootimg mesa-dri-swrast"
+makedepends="devicepkg-dev"
+source="deviceinfo"
+
+build() {
+	devicepkg_build $startdir $pkgname
+}
+
+package() {
+	devicepkg_package $startdir $pkgname
+}
+
+
+sha512sums="17c9409c7c6284632bc71ff1b9022afa7cb9ff9333cd8820787bde99cef1e3ec03f4910d297106e7706374c6d9406ce197c33fd371858e96e8e34c086dd863ff  deviceinfo"