build: install into bin instead of sbin

Installs into bin instead of sbin per guidelines.

Signed-off-by: Patrick Venture <venture@google.com>
Change-Id: I2f61cbda4721533610516c0c91da4b3a16d15b52
diff --git a/Makefile.am b/Makefile.am
index 205c708..1010533 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,6 +1,6 @@
 AM_DEFAULT_SOURCE_EXT = .cpp
 
-sbin_PROGRAMS = phosphor-timemanager
+bin_PROGRAMS = phosphor-timemanager
 
 noinst_LTLIBRARIES = libtimemanager.la