fastbootd: Enable erase and flash commands for physical partitions.

Bug: 78793464
Test: adb reboot fastboot && fastboot flashall

Change-Id: Ibe802c36f6efe20111a2315616ef34d3a027950f
diff --git a/fastboot/device/variables.h b/fastboot/device/variables.h
index 45c6dc9..88947e0 100644
--- a/fastboot/device/variables.h
+++ b/fastboot/device/variables.h
@@ -34,3 +34,4 @@
 bool GetMaxDownloadSize(FastbootDevice* device, const std::vector<std::string>& args);
 bool GetUnlocked(FastbootDevice* device, const std::vector<std::string>& args);
 bool GetHasSlot(FastbootDevice* device, const std::vector<std::string>& args);
+bool GetPartitionSize(FastbootDevice* device, const std::vector<std::string>& args);