[PATCH v5 13/27] x86/boot/64: Build head64.c as mcmodel large when PIE is enabled

The __startup_64 function assumes all symbols have relocated addresses instead of the current boot virtual address. PIE generated code favor relative addresses making all virtual and physical address math incorrect. If PIE is enabled, build head64.c as mcmodel large instead to ensure absolute

[PATCH v5 13/27] x86/boot/64: Build head64.c as mcmodel large when PIE is enabled

The __startup_64 function assumes all symbols have relocated addresses instead of the current boot virtual address. PIE generated code favor relative addresses making all virtual and physical address math incorrect. If PIE is enabled, build head64.c as mcmodel large instead to ensure absolute