mm: memblock: add more debug logs

It is useful to know the exact caller of memblock_phys_alloc_range() to
track early memory reservations during development.

Currently, when memblock debugging is enabled, the allocations done with
memblock_phys_alloc_range() are only reported at memblock_reserve():

[    0.000000] memblock_reserve: [0x000000023fc6b000-0x000000023fc6bfff] memblock_alloc_range_nid+0xc0/0x188

Add memblock_dbg() to memblock_phys_alloc_range() to get details about
its usage.

For example:

[    0.000000] memblock_phys_alloc_range: 4096 bytes align=0x1000 from=0x0000000000000000 max_addr=0x0000000000000000 early_pgtable_alloc+0x24/0x178
[    0.000000] memblock_reserve: [0x000000023fc6b000-0x000000023fc6bfff] memblock_alloc_range_nid+0xc0/0x188

Signed-off-by: Faiyaz Mohammed <faiyazm@codeaurora.org>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>

mm/memblock.c

@@ -1419,6 +1419,9 @@ phys_addr_t __init memblock_phys_alloc_range(phys_addr_t size,
 					     phys_addr_t start,
 					     phys_addr_t end)
 {
+	memblock_dbg("%s: %llu bytes align=0x%llx from=%pa max_addr=%pa %pS\n",
+		     __func__, (u64)size, (u64)align, &start, &end,
+		     (void *)_RET_IP_);
 	return memblock_alloc_range_nid(size, align, start, end, NUMA_NO_NODE,
 					false);
 }