These headers define the context types that alternative implementations must
provide. The context types are dummy types, suitable for building but not
meant to be usable by an implementation.
This is the output of the following script:
```
perl -0777 -ne '
m@^#if !defined\((MBEDTLS_\w+_ALT)\).*\n((?:.*\n)*?)#else.*\n#include "(.*_alt\.h)"\n#endif@m or next;
$symbol = $1; $content = $2; $header = $3;
$header_symbol = $header; $header_symbol =~ y/a-z./A-Z_/;
m@/\*[ *\n]*Copyright .*?\*/@s or die; $copyright = $&;
open OUT, ">tests/include/alt-dummy/$header" or die;
$content =~ s@//.*@@mg;
$content =~ s@/\*.*?\*/@@sg;
$content =~ s@\{.*?\}@{\n int dummy;\n}@sg;
$content =~ s@ +$@@mg;
$content =~ s@\n{3,}@\n\n@g; $content =~ s@\A\n+@@; $content =~ s@\n*\Z@\n@;
print OUT "/* $header with dummy types for $symbol */\n$copyright\n\n#ifndef $header_symbol\n#define $header_symbol\n\n$content\n\n#endif /* $header */\n" or die;
close OUT or die;
' include/mbedtls/*.h
```
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
