PLDM:Use new alias of DBUS_TIMEOUT for bus.call

This commit uses a new global variable for DBUS_TIMEOUT which is included as an input parameter for bus.call dbus calls. The new alias makes the bus.call function shorter and readable.

Change-Id: I336c97bc0631d5370ff3648e41f50e3e283d771b
Signed-off-by: vkaverap@in.ibm.com <vkaverap@in.ibm.com>
diff --git a/libpldmresponder/bios_config.cpp b/libpldmresponder/bios_config.cpp
index dec7b3f..e4b10c8 100644
--- a/libpldmresponder/bios_config.cpp
+++ b/libpldmresponder/bios_config.cpp
@@ -514,9 +514,7 @@
                                           "org.freedesktop.DBus.Properties",
                                           "Get");
         method.append(biosInterface, "BaseBIOSTable");
-        auto reply = bus.call(
-            method,
-            std::chrono::duration_cast<microsec>(sec(DBUS_TIMEOUT)).count());
+        auto reply = bus.call(method, dbusTimeout);
         std::variant<BaseBIOSTable> varBiosTable{};
         reply.read(varBiosTable);
         biosTable = std::get<BaseBIOSTable>(varBiosTable);