[X3] Global shadowing warnings

[ibis-hdl]

Using MSVC with enabled Warning /W4 I get the warning on Boost 1.78

H:.conan\short\8c1894\1\include\boost\spirit\home\x3\auxiliary\any_parser.hpp(121): warning C4459: Declaration of "attr" hides global Declaration
H:.conan\short\8c1894\1\include\boost\spirit\home\x3\auxiliary\attr.hpp(126): note: see Declaration of "boost::spirit::x3::attr"

H:.conan\short\8c1894\1\include\boost\spirit\home\x3\support\no_case.hpp(56): warning C4459: Declaration of "char_type" hides global Declaration
H:.conan\short\8c1894\1\include\boost\spirit\home\x3\char\char.hpp(20): note: see Declaration of "boost::spirit::x3::standard::char_type"

I haven't checked it with v1.80 yet. Please fix the naming so once is able to compile with higher warning levels on MSVC; otherwise close this issue please.

[Kojoley]

Fixing global shadowing warnings is on my TODO, but at very low priority due to little value and high intrusiveness of the fix.