contrib/systemd/osmo-trx-uhd: fix HOME=

With recent changes, osmo-trx-uhd does not run as root anymore. Change
HOME=%h, which evaluates to HOME=/root, to HOME=%S/osmocom which
evaluates to HOME=/var/lib/osmocom. This is the StateDirectory that is
owned by the osmocom user.

Fix for:
  osmo-trx-uhd[4013]: terminate called after throwing an instance of 'boost::filesystem::filesystem_error'
  osmo-trx-uhd[4013]:   what():  boost::filesystem::status: Permission denied: "/root/.config/uhd.conf"
  osmo-trx-uhd[4013]: signal 6 received

Fixes: OS#6495
Change-Id: Ic6f020dd800eedc5e56c7d71e65521ec831d8c64
---
M contrib/systemd/osmo-trx-uhd.service
1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/contrib/systemd/osmo-trx-uhd.service b/contrib/systemd/osmo-trx-uhd.service
index 64eb510..50440a7 100644
--- a/contrib/systemd/osmo-trx-uhd.service
+++ b/contrib/systemd/osmo-trx-uhd.service
@@ -8,7 +8,7 @@
 Restart=always
 StateDirectory=osmocom
 WorkingDirectory=%S/osmocom
-Environment=HOME=%h
+Environment=HOME=%S/osmocom
 User=osmocom
 Group=osmocom
 ExecStart=/usr/bin/osmo-trx-uhd -C /etc/osmocom/osmo-trx-uhd.cfg

