x86/mm: Carve out INVLPG inline asm for use by others

No functional changes.

Signed-off-by: Borislav Petkov (AMD) <[e-mail]>
Link: https://lore.kernel.org/r/ZyulbYuvrkshfsd2@antipodes

arch/x86/include/asm/tlb.h

···
 	free_page_and_swap_cache(table);
 }
 
+static inline void invlpg(unsigned long addr)
+{
+	asm volatile("invlpg (%0)" ::"r" (addr) : "memory");
+}
 #endif /* _ASM_X86_TLB_H */

arch/x86/mm/tlb.c

···
 #include <asm/cacheflush.h>
 #include <asm/apic.h>
 #include <asm/perf_event.h>
+#include <asm/tlb.h>
 
 #include "mm_internal.h"
 
···
 	bool cpu_pcide;
 
 	/* Flush 'addr' from the kernel PCID: */
-	asm volatile("invlpg (%0)" ::"r" (addr) : "memory");
+	invlpg(addr);
 
 	/* If PTI is off there is no user PCID and nothing to flush. */
 	if (!static_cpu_has(X86_FEATURE_PTI))