修复使能kdump时潜在的启动阶段挂死问题

【标题描述】for_each_mem_range()和__map_memblock()参数end的值，都是start+size，而不是start+size-1。如果低4G物理内存结束地址恰好处在4G边界，且没有起始地址=4G的高4G内存块，即有内存块[start,4G）。由于当前按start+size-1处理了，则在将[start,4G）按页映射后，调整start=SZ_4G，此时start=end=SZ_4G，在__map_memblock()中处理将出错。
【环境信息】arm64
【问题复现步骤】
1、使用4G内存的vm进行测试，grub.cfg中配置参数mem=3584M crashkernel=512M
2、重启vm
出现概率(是否必现，概率性错误) 在此配置下必现，其它配置没有复现过
【预期结果】内核正常启动
【实际结果】内核启动失败
[    0.000000][    T0] ------------[ cut here ]------------
[    0.000000][    T0] kernel BUG at arch/arm64/mm/mmu.c:262!
[    0.000000][    T0] Internal error: Oops - BUG: 0 [#1] SMP
[    0.000000][    T0] Modules linked in:
[    0.000000][    T0] CPU: 0 PID: 0 Comm: swapper Not tainted 5.10.0+ #4
[    0.000000][    T0] Hardware name: linux,dummy-virt (DT)
[    0.000000][    T0] pstate: 60000085 (nZCv daIf -PAN -UAO -TCO BTYPE=--)
[    0.000000][    T0] pc : alloc_init_cont_pmd+0x168/0x174
[    0.000000][    T0] lr : alloc_init_pud+0x118/0x25c
[    0.000000][    T0] sp : ffffb53055613d10
[    0.000000][    T0] x29: ffffb53055613d10 x28: fffffdfffe433c00
[    0.000000][    T0] x27: ffff12e000000000 x26: 0000000100000000
[    0.000000][    T0] x25: ffff12e01fffffff x24: 0068000100000f05
[    0.000000][    T0] x23: 0000000000000003 x22: 0068000000000f03
[    0.000000][    T0] x21: ffffb53055179564 x20: ffff12e020000000
[    0.000000][    T0] x19: ffff12e020000000 x18: ffffffffffffffff
[    0.000000][    T0] x17: 0000000000000000 x16: 0000000000001800
[    0.000000][    T0] x15: ffffb53055613b08 x14: ffffffffffffffff
[    0.000000][    T0] x13: 0000000000000080 x12: ffffb53055613ea4
[    0.000000][    T0] x11: 0000000000000003 x10: 0000000000000002
[    0.000000][    T0] x9 : 0000000000000180 x8 : 0000000000000002
[    0.000000][    T0] x7 : 0068000100000f05 x6 : 0000000000000003
[    0.000000][    T0] x5 : ffffb53055179564 x4 : 0068000000000f03
[    0.000000][    T0] x3 : 0000000100000000 x2 : ffff12e020000000
[    0.000000][    T0] x1 : ffff12e000000000 x0 : 0000000000000001
[    0.000000][    T0] Call trace:
[    0.000000][    T0]  alloc_init_cont_pmd+0x168/0x174
[    0.000000][    T0]  alloc_init_pud+0x118/0x25c
[    0.000000][    T0]  __create_pgd_mapping+0xa4/0xf4
[    0.000000][    T0]  __map_memblock+0x40/0x4c
[    0.000000][    T0]  map_mem+0x214/0x264
[    0.000000][    T0]  paging_init+0xa0/0x338
[    0.000000][    T0]  setup_arch+0x2bc/0x368
[    0.000000][    T0]  start_kernel+0x98/0x4f0
[    0.000000][    T0] Code: d5033fdf f9400380 92400400 17ffffbd (d4210000)
[    0.000000][    T0] random: get_random_bytes called from oops_exit+0x40/0x7c with crng_init=0
[    0.000000][    T0] ---[ end trace 0000000000000000 ]---
[    0.000000][    T0] Kernel panic - not syncing: Oops - BUG: Fatal exception
[    0.000000][    T0] ---[ end Kernel panic - not syncing: Oops - BUG: Fatal exception ]---

【附件信息】无

GVP openEuler/kernel

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GVPopenEuler/kernel

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