kernel: bump 4.19 to 4.19.122

Refreshed all patches.

Remove upstreamed:
- 551-loop-Better-discard-support-for-block-devices.patch

Fixed:
- CVE-2020-11884
- CVE-2020-12114
- CVE-2019-3016
- CVE-2020-11669

Compile-tested on: cns3xxx
Runtime-tested on: cns3xxx

Signed-off-by: Koen Vandeputte <koen.vandeputte@ncentric.com>

target/linux/bcm47xx/patches-4.19/159-cpu_fixes.patch

@@ -488,7 +488,7 @@
  		uasm_i_eret(&p); /* return from trap */
  	}
  #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
-@@ -2046,6 +2055,9 @@ build_r4000_tlbchange_handler_head(u32 *
+@@ -2049,6 +2058,9 @@ build_r4000_tlbchange_handler_head(u32 *
  #ifdef CONFIG_64BIT
  	build_get_pmde64(p, l, r, wr.r1, wr.r2); /* get pmd in ptr */
  #else
@@ -498,7 +498,7 @@
  	build_get_pgde32(p, wr.r1, wr.r2); /* get pgd in ptr */
  #endif
  
-@@ -2092,6 +2104,9 @@ build_r4000_tlbchange_handler_tail(u32 *
+@@ -2095,6 +2107,9 @@ build_r4000_tlbchange_handler_tail(u32 *
  	build_tlb_write_entry(p, l, r, tlb_indexed);
  	uasm_l_leave(l, *p);
  	build_restore_work_registers(p);