[fpc-pascal] TProcess doc page bugs

[Alexey Tor.]

https://www.freepascal.org/docs-html/current/fcl/process/tprocess.readinputstream.html

a) it has 2 sections "Arguments" (mixed with "Func result")- pls make 
nicer output:

"Arguments (variant 1)", "Arguments (variant 2)", "Function result"

b) first variant of func has "public" mark - it's crap here

c) 'Read available data from input stream" - it's for Input? for 
Input/Output/Stderr? --> change to "Read available data from one of 
process streams"

Alexey Torgashin