runtime: arm64 skippage6.sh test fails to JIT code when page size > 4KB

Cannot encode 15552 as an immediate (with #40435).

/Users/steve/git/runtime/artifacts/tests/coreclr/OSX.arm64.Debug/JIT/Methodical/largeframes/skip6/skippage6/skippage6.sh

Assert failure(PID 49620 [0x0000c1d4], Thread: 690896 [0xa8ad0]): Assertion failed '!"Instruction cannot be encoded: IF_DI_2A"' in 'BigFrames.Test:Test1(int)' during 'Generate code' (IL size 23715)

    File: /Users/steve/git/runtime/src/coreclr/src/jit/emitarm64.cpp Line: 5598
    Image: /Users/steve/git/runtime/artifacts/tests/coreclr/OSX.arm64.Debug/Tests/Core_Root/corerun

/Users/steve/git/runtime/artifacts/tests/coreclr/OSX.arm64.Debug/JIT/Methodical/largeframes/skip6/skippage6/skippage6.sh: line 356: 49620 Abort trap: 6           $LAUNCHER $ExePath "${CLRTestExecutionArguments[@]}"
BEGIN EXECUTION
/Users/steve/git/runtime/artifacts/tests/coreclr/OSX.arm64.Debug/Tests/Core_Root/corerun skippage6.dll ''
Expected: 100
Actual: 134
END EXECUTION - FAILED

    frame #2: 0x0000000123d6d1b4 libclrjit.dylib`::assertAbort(why="!\"Instruction cannot be encoded: IF_DI_2A\"", file="/Users/steve/git/runtime/src/coreclr/src/jit/emitarm64.cpp", line=5598) at error.cpp:294:9
    frame #3: 0x0000000123f92340 libclrjit.dylib`emitter::emitIns_R_R_I(this=0x00000001007e5000, ins=INS_sub, attr=EA_8BYTE, reg1=REG_ZR, reg2=REG_ZR, imm=15552, opt=INS_OPTS_NONE) at emitarm64.cpp:5598:13
  * frame #4: 0x0000000123e4447c libclrjit.dylib`CodeGen::inst_RV_IV(this=0x00000001007e4a78, ins=INS_sub, reg=REG_SP, val=15552, size=EA_8BYTE, flags=INS_FLAGS_DONT_CARE) at instr.cpp:521:19
    frame #5: 0x0000000123f6ad70 libclrjit.dylib`CodeGen::genStackPointerConstantAdjustment(this=0x00000001007e4a78, spDelta=-15552) at codegenarmarch.cpp:42:5

/cc @sandreenko @JulieLeeMSFT

category:correctness theme:prolog-epilog skill-level:intermediate cost:small