build: pkg anti-pattern: use defaults

Use the defaults in the pkg check where the default error message is
sufficient to identify which package is missing.

Change-Id: Ib3c000db8dc8c4f9efedb66464c86d8d8c25bacb
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/configure.ac b/configure.ac
index 7477a9d..0347604 100644
--- a/configure.ac
+++ b/configure.ac
@@ -45,10 +45,10 @@
     [${srcdir}/gen_makefile.sh ${srcdir} "$myChips" > Makefile.generated],
     [myChips="$CHIPS"])
 
-PKG_CHECK_MODULES([SYSTEMD], [libsystemd >= 221], [], [AC_MSG_ERROR(["systemd required and not found"])])
-PKG_CHECK_MODULES([PHOSPHOR_LOGGING], [phosphor-logging],, [AC_MSG_ERROR([Could not find phosphor-logging...openbmc/phosphor-logging package required])])
-PKG_CHECK_MODULES([PHOSPHOR_DBUS_INTERFACES], [phosphor-dbus-interfaces], [], [AC_MSG_ERROR(["phosphor-dbus-interfaces required and not found."])])
-PKG_CHECK_MODULES([OPENPOWER_DBUS_INTERFACES], [openpower-dbus-interfaces], [], [AC_MSG_ERROR(["openpower-dbus-interfaces required and not found."])])
+PKG_CHECK_MODULES([SYSTEMD], [libsystemd >= 221])
+PKG_CHECK_MODULES([PHOSPHOR_LOGGING], [phosphor-logging])
+PKG_CHECK_MODULES([PHOSPHOR_DBUS_INTERFACES], [phosphor-dbus-interfaces])
+PKG_CHECK_MODULES([OPENPOWER_DBUS_INTERFACES], [openpower-dbus-interfaces])
 
 PKG_PROG_PKG_CONFIG
 AC_ARG_WITH([systemdsystemunitdir],