soc-qcom-msm8916: fix build

Fix for:
  >>> soc-qcom-msm8916-rproc*: Running split function rproc...
  install: can't stat 'q6voiced.conf': No such file or directory

Part-of: <https://gitlab.postmarketos.org/postmarketOS/pmaports/-/merge_requests/7511>

device/testing/soc-qcom-msm8916/APKBUILD

@@ -3,7 +3,7 @@
 pkgname=soc-qcom-msm8916
 pkgdesc="Common package for Qualcomm MSM8916 devices"
 pkgver=25
-pkgrel=0
+pkgrel=1
 url="https://postmarketos.org"
 license="BSD-3-Clause"
 arch="aarch64 armv7"
@@ -51,7 +51,7 @@ rproc() {
 	depends="msm-modem msm-modem-uim-selection q6voiced"
 	replaces="$pkgname-modem $pkgname-rproc_none $pkgname-rproc_no_modem $pkgname-rproc_all"
 
-	install -Dm644 q6voiced.conf "$subpkgdir"/etc/conf.d/q6voiced
+	install -Dm644 "$srcdir"/q6voiced.conf "$subpkgdir"/etc/conf.d/q6voiced
 }
 
 rproc_openrc() {