Reflect rust#133422 & rust#133587 to inline assembly documentation

[taiki-e]

• Fix clobber_abi in RV32E and RV64E inline assembly rust#133422
• Fix handling of x18 in AArch64 inline assembly on ohos/trusty or with -Zfixed-x18 rust#133463 EDIT: there is no specific target list in docs and -Zfixed-x18 is unstable, so this doesn't need doc update
• Fix target_feature handling in freg of LoongArch inline assembly rust#133587

These make some sections in inline assembly documentation, such as clobber_abi, out of date.