radv: Fix driver UUID SHA1 init.

Was missing the init, found by Emil.

Fixes: d17443a459 "radv: Use build ID if available for cache UUID."
CC: <mesa-stable@lists.freedesktop.org>
Reviewed-by: Eric Engestrom <eric.engestrom@intel.com>
Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>

src/amd/vulkan/radv_device.c

@@ -77,7 +77,9 @@ radv_device_get_cache_uuid(enum radeon_family family, void *uuid)
 	struct mesa_sha1 ctx;
 	unsigned char sha1[20];
 	unsigned ptr_size = sizeof(void*);
+
 	memset(uuid, 0, VK_UUID_SIZE);
+	_mesa_sha1_init(&ctx);
 
 	if (!radv_get_build_id(radv_device_get_cache_uuid, &ctx) ||
 	    !radv_get_build_id(LLVMInitializeAMDGPUTargetInfo, &ctx))