Revamp the dynamic library shim

This switches the default llama.cpp to be CPU based, and builds the GPU variants
as dynamically loaded libraries which we can select at runtime.

This also bumps the ROCm library to version 6 given 5.7 builds don't work
on the latest ROCm library that just shipped.

gpu/types.go

@@ -3,6 +3,7 @@ package gpu
 // Beginning of an `ollama info` command
 type GpuInfo struct {
 	Driver      string `json:"driver,omitempty"`
+	Library     string `json:"library,omitempty"`
 	TotalMemory uint64 `json:"total_memory,omitempty"`
 	FreeMemory  uint64 `json:"free_memory,omitempty"`