Compilation issues when compiling under HP-UX B.11.31.

Two compilation issues with freetds-0.95.89 (as well as .88 and .80) when
compiling under HP-UX B.11.31 with the "HP C/aC++ B3910B A.06.20 [May 13
2008]" compiler in 32-bit mode.  Both have simple work-arounds which are
fine for my requirements, but I thought I'd report them to be addressed
when time permits.

src/tds/token.c generates a 'warning #2513-D: a value of type "int" cannot
be assigned to an entity of type "char *" because <alloca.h> has not been
#included:
        nbcbuf = alloca((info->num_cols + 7) / 8);
               ^

Simply adding an "#include <alloca.h>" to token.c solves the issue.  I did
not include a patch file because I imagine that this would most properly be
resolved via configure/config.h rather than unconditionally adding it to
token.c.  (In the version of Linux I use, <stdlib.h> performs an #include
of <alloca.h> with the default compiler defines, so a prototype is present
and gcc produces no similar warning.)


The second issue is with src/dblib/dbpivot.c, which generates a large
number of 'error #2136: struct "col_t" has no field "XX" errors due to the
anonymous union in struct col_t's definition.  A Google search implies that
anonymous unions were once a gcc extension but were adopted in C11; the
HP-UX compiler only accepts up to and including C99.

My work-around was to assign a name to the union and then update references
to the union members with this union name.  I am not including a patch
because I just named the union "x" and do not know what a more logical name
for the union might be.