attestation: remove sed modification of attestation.conf

After the changes in
https://chromium-review.googlesource.com/c/chromiumos/overlays/chromiumos-overlay/+/2105818,
a sed modification is made unconditionally to attestationd.conf. Make
the changes directly in attestationd.conf instead.

BUG=none
TEST=emerge attestation and verify that attestationd.conf has "started tpm_managerd" instead of "started tcsd"

Cq-Depend: chromium:2288071
Change-Id: I4e491284080521e395641964784a0bd5575a9cba
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/chromiumos-overlay/+/2288249
Reviewed-by: Leo Lai <cylai@google.com>
Tested-by: Nicholas Bishop <nbishop@neverware.com>
Commit-Queue: Leo Lai <cylai@google.com>
diff --git a/chromeos-base/attestation/attestation-9999.ebuild b/chromeos-base/attestation/attestation-9999.ebuild
index d361f3e..6ce2420 100644
--- a/chromeos-base/attestation/attestation-9999.ebuild
+++ b/chromeos-base/attestation/attestation-9999.ebuild
@@ -60,9 +60,6 @@
 
 	insinto /etc/init
 	doins server/attestationd.conf
-	sed -i 's/started tcsd/started tpm_managerd/' \
-		"${D}/etc/init/attestationd.conf" ||
-		die "Can't replace tcsd with tpm_managerd in attestationd.conf"
 
 	dosbin "${OUT}"/attestationd
 	dobin "${OUT}"/attestation_client