riscv: mm: Fix prototype to avoid discarding const

__flush_tlb_range() does not modify the provided cpumask, so its cmask
parameter can be pointer-to-const. This avoids the unsafe cast of
cpu_online_mask.

Fixes: 54d7431a ("riscv: Add support for BATCHED_UNMAP_TLB_FLUSH")
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20240301201837.2826172-1-samuel.holland@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>

arch/riscv/mm/tlbflush.c

@@ -99,7 +99,7 @@ static void __ipi_flush_tlb_range_asid(void *info)
 	local_flush_tlb_range_asid(d->start, d->size, d->stride, d->asid);
 }
 
-static void __flush_tlb_range(struct cpumask *cmask, unsigned long asid,
+static void __flush_tlb_range(const struct cpumask *cmask, unsigned long asid,
 			      unsigned long start, unsigned long size,
 			      unsigned long stride)
 {
@@ -200,7 +200,7 @@ void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
 
 void flush_tlb_kernel_range(unsigned long start, unsigned long end)
 {
-	__flush_tlb_range((struct cpumask *)cpu_online_mask, FLUSH_TLB_NO_ASID,
+	__flush_tlb_range(cpu_online_mask, FLUSH_TLB_NO_ASID,
 			  start, end - start, PAGE_SIZE);
 }