arm64: add ioremap physical address information

In /proc/vmallocinfo, it's good to show the physical address
of each ioremap in vmallocinfo. Add physical address information
in arm64 ioremap.

0xffffc900047f2000-0xffffc900047f4000    8192 _nv013519rm+0x57/0xa0
[nvidia] phys=f8100000 ioremap
0xffffc900047f4000-0xffffc900047f6000    8192 _nv013519rm+0x57/0xa0
[nvidia] phys=f8008000 ioremap
0xffffc90004800000-0xffffc90004821000  135168 e1000_probe+0x22c/0xb95
[e1000e] phys=f4300000 ioremap
0xffffc900049c0000-0xffffc900049e1000  135168 _nv013521rm+0x4d/0xd0
[nvidia] phys=e0140000 ioremap

Signed-off-by: Min-Hua Chen <orca.chen@gmail.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm64/mm/ioremap.c

@@ -62,6 +62,7 @@ static void __iomem *__ioremap_caller(phys_addr_t phys_addr, size_t size,
 	if (!area)
 		return NULL;
 	addr = (unsigned long)area->addr;
+	area->phys_addr = phys_addr;
 
 	err = ioremap_page_range(addr, addr + size, phys_addr, prot);
 	if (err) {