Update the RyuJIT IR documentation.
Update the RyuJIT IR documentation.

The most important parts of these changes update the description of the
IR to cover HIR, LIR, and the differences between the two. Other updates
include some minor restructuring, typo fixes, rephrasings, and JIT dump
refreshes.

gkhanna79/coreclr,poizan42/coreclr,dpodder/coreclr,kyulee1/coreclr,krk/coreclr,rartemev/coreclr,kyulee1/coreclr,mskvortsov/coreclr,tijoytom/coreclr,dpodder/coreclr,JonHanna/coreclr,JonHanna/coreclr,mskvortsov/coreclr,yizhang82/coreclr,YongseopKim/coreclr,poizan42/coreclr,wateret/coreclr,poizan42/coreclr,YongseopKim/coreclr,kyulee1/coreclr,wateret/coreclr,poizan42/coreclr,cydhaselton/coreclr,krk/coreclr,krk/coreclr,krk/coreclr,AlexGhiondea/coreclr,mskvortsov/coreclr,mmitche/coreclr,JonHanna/coreclr,AlexGhiondea/coreclr,ragmani/coreclr,mskvortsov/coreclr,russellhadley/coreclr,rartemev/coreclr,mmitche/coreclr,kyulee1/coreclr,hseok-oh/coreclr,mmitche/coreclr,yizhang82/coreclr,YongseopKim/coreclr,ruben-ayrapetyan/coreclr,rartemev/coreclr,dpodder/coreclr,tijoytom/coreclr,hseok-oh/coreclr,ruben-ayrapetyan/coreclr,AlexGhiondea/coreclr,parjong/coreclr,russellhadley/coreclr,gkhanna79/coreclr,botaberg/coreclr,YongseopKim/coreclr,hseok-oh/coreclr,hseok-oh/coreclr,wtgodbe/coreclr,tijoytom/coreclr,cshung/coreclr,gkhanna79/coreclr,JonHanna/coreclr,gkhanna79/coreclr,cydhaselton/coreclr,cshung/coreclr,russellhadley/coreclr,hseok-oh/coreclr,tijoytom/coreclr,cydhaselton/coreclr,AlexGhiondea/coreclr,botaberg/coreclr,mskvortsov/coreclr,rartemev/coreclr,cshung/coreclr,JosephTremoulet/coreclr,krk/coreclr,JonHanna/coreclr,cshung/coreclr,JonHanna/coreclr,mmitche/coreclr,dpodder/coreclr,botaberg/coreclr,botaberg/coreclr,wtgodbe/coreclr,ragmani/coreclr,russellhadley/coreclr,poizan42/coreclr,parjong/coreclr,ruben-ayrapetyan/coreclr,wtgodbe/coreclr,ruben-ayrapetyan/coreclr,russellhadley/coreclr,mmitche/coreclr,yizhang82/coreclr,JosephTremoulet/coreclr,JosephTremoulet/coreclr,wateret/coreclr,wtgodbe/coreclr,cydhaselton/coreclr,tijoytom/coreclr,rartemev/coreclr,yizhang82/coreclr,ragmani/coreclr,wtgodbe/coreclr,dpodder/coreclr,AlexGhiondea/coreclr,AlexGhiondea/coreclr,wateret/coreclr,kyulee1/coreclr,ragmani/coreclr,wtgodbe/coreclr,botaberg/coreclr,parjong/coreclr,rartemev/coreclr,cydhaselton/coreclr,russellhadley/coreclr,gkhanna79/coreclr,yizhang82/coreclr,wateret/coreclr,krk/coreclr,cydhaselton/coreclr,YongseopKim/coreclr,tijoytom/coreclr,yizhang82/coreclr,cshung/coreclr,JosephTremoulet/coreclr,hseok-oh/coreclr,mmitche/coreclr,wateret/coreclr,ruben-ayrapetyan/coreclr,JosephTremoulet/coreclr,mskvortsov/coreclr,parjong/coreclr,parjong/coreclr,YongseopKim/coreclr,poizan42/coreclr,ragmani/coreclr,ruben-ayrapetyan/coreclr,JosephTremoulet/coreclr,gkhanna79/coreclr,cshung/coreclr,botaberg/coreclr,ragmani/coreclr,kyulee1/coreclr,dpodder/coreclr,parjong/coreclr