Update Linux to v5.4.148

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.4.148.tar.gz

Change-Id: Ib3d26c5ba9b022e2e03533005c4fed4d7c30b61b
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 573463d..d49e334 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -98,7 +98,7 @@
 	for_each_memblock(memory, reg) {
 		phys_addr_t end = reg->base + reg->size;
 
-		if (reg->base <= vmlinux_end && vmlinux_end <= end) {
+		if (reg->base <= vmlinux_start && vmlinux_end <= end) {
 			mem_size = min(reg->size, (phys_addr_t)-PAGE_OFFSET);
 
 			/*
@@ -115,8 +115,9 @@
 	/* Reserve from the start of the kernel to the end of the kernel */
 	memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
 
-	set_max_mapnr(PFN_DOWN(mem_size));
-	max_low_pfn = PFN_DOWN(memblock_end_of_DRAM());
+	max_pfn = PFN_DOWN(memblock_end_of_DRAM());
+	max_low_pfn = max_pfn;
+	set_max_mapnr(max_low_pfn);
 
 #ifdef CONFIG_BLK_DEV_INITRD
 	setup_initrd();
@@ -166,12 +167,11 @@
 
 	ptep = &fixmap_pte[pte_index(addr)];
 
-	if (pgprot_val(prot)) {
+	if (pgprot_val(prot))
 		set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot));
-	} else {
+	else
 		pte_clear(&init_mm, addr, ptep);
-		local_flush_tlb_page(addr);
-	}
+	local_flush_tlb_page(addr);
 }
 
 static pte_t *__init get_pte_virt(phys_addr_t pa)