main/acpi: adopt APKBUILD

https://lists.alpinelinux.org/~alpine/aports/patches/2996

main/acpi/APKBUILD

-# Maintainer: Cág <ca6c@bitmessage.ch>
+# Maintainer: Drew DeVault <sir@cmpwn.com>
 pkgname=acpi
 pkgver=1.7
-pkgrel=3
+pkgrel=4
 pkgdesc="ACPI client for battery, power, and thermal readings"
 url="https://sourceforge.net/projects/acpiclient/files/acpiclient/"
 arch="all"
 options="!check"  # No test suite.
 license="GPL-2.0-or-later"
 subpackages="$pkgname-doc"
-source="https://downloads.sourceforge.net/acpiclient/$pkgname-$pkgver.tar.gz"
+source="https://downloads.sourceforge.net/acpiclient/acpi-$pkgver.tar.gz"
 
 build() {
-	cd "$builddir"
 	./configure \
 		--build=$CBUILD \
 		--host=$CHOST \
@@ -23,7 +22,6 @@ build() {
 }
 
 package() {
-	cd "$builddir"
 	make DESTDIR="$pkgdir" install
 }