smbios-mdr: Add custom dbus object path

The patch adds a configurable meson option which when enabled,
customizes the dbus object path.

Earlier efforts where made to have similar functionality and
the some  MRs for same were rejected for various reasons
[1] https://gerrit.openbmc.org/c/openbmc/smbios-mdr/+/46129
[2] https://gerrit.openbmc.org/c/openbmc/bmcweb/+/46739
[3] https://gerrit.openbmc.org/c/openbmc/entity-manager/+/44196

Tested:

1) Dbus tree output
```
/xyz/openbmc_project
|-/xyz/openbmc_project/inventory
|`-/xyz/openbmc_project/inventory/system
|`-/xyz/openbmc_project/inventory/system/chassis
||-/xyz/openbmc_project/inventory/system/chassis/Chassis_0
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot0
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot1
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot10
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot11
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot12
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot13
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot14
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot15
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot16
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot17
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot18
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot19
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot2
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot3
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot4
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot5
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot6
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot7
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot8
|||- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/pcieslot9
||`- /xyz/openbmc_project/inventory/system/chassis/Chassis_0/tpm0
```

Change-Id: I765e56a30c3e5712c2f43fc6a8302be5cc9d9a96
Signed-off-by: Prithvi Pai <ppai@nvidia.com>
diff --git a/src/meson.build b/src/meson.build
index d94397e..1094835 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -27,6 +27,10 @@
     cpp_args_smbios += ['-DEXPOSE_FW_COMPONENT_NAME']
 endif
 
+if get_option('custom-dbus-path').allowed()
+    cpp_args_smbios += ['-DCUSTOM_DBUS_PATH']
+endif
+
 executable(
     'smbiosmdrv2app',
     'mdrv2.cpp',