Fix the condition, register and immediate of arm32 cmp, cmn, tst and teq ##arch - #27141

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Description

cmp , cmn , tst and teq with an immediate dropped the condition , and above 255 also the register :

• the immediate path ORed 0xe2 into the low byte . the 2 is the I bit , the e is the al condition , and it was ORed over the condition that was already there , so eq came out as al , and anything with the top bit , like le , as nv
• values above 255 went to findyz , which did not set Rn and computed the rotation wrong . it had no other caller , so it is gone , and the value goes through getimmed8 , the same encoder mov uses , which refuses what has no 8 bit rotated form
• the #imm8, #rot form keeps its own path , only checked to fit in 8 bits now , and a bad first register is refused instead of OR'd in as -1

found by decoding random words with llvm-mc ( -triple=armv7 ) , assembling the text with rasm2 -a arm -b 32 and decoding the result again . same as llvm went from 618 to 659 of 3459 : 22 that were wrong and 19 that findyz refused , nothing that was right changed . the 6 new lines in db/asm/arm_32 fail before the change . the new test in db/tools/rasm2 pins that a value with no encoding ( tst r0, 0x101 ) is refused , master refused it too but also logged Parameter 257 out of range (0-255) . db/asm has no failures .

the tests are added next to the other compare tests and not at the end of the files , so this does not conflict with #27137 or #27140 , which touch other parts of armass.c .