ATTRIBUTE_HIDDEN for libbfd.h

[Andreas Schwab]

Breaks --enable-shared build:

/bin/sh ./libtool --tag=CC   --mode=link gcc -W -Wall -Wstrict-prototypes -Wmissing-prototypes -Wshadow -Werror -Wwrite-strings  -O2 -g  -static-libstdc++ -static-libgcc  -o as-new app.o as.o atof-generic.o compress-debug.o cond.o depend.o dwarf2dbg.o dw2gencfi.o ecoff.o ehopt.o expr.o flonum-copy.o flonum-konst.o flonum-mult.o frags.o hash.o input-file.o input-scrub.o listing.o literal.o macro.o messages.o output-file.o read.o remap.o sb.o stabs.o subsegs.o symbols.o write.o tc-i386.o obj-elf.o atof-ieee.o  ../opcodes/libopcodes.la ../bfd/libbfd.la ../libiberty/libiberty.a   -ldl 
libtool: link: gcc -W -Wall -Wstrict-prototypes -Wmissing-prototypes -Wshadow -Werror -Wwrite-strings -O2 -g -static-libstdc++ -static-libgcc -o .libs/as-new app.o as.o atof-generic.o compress-debug.o cond.o depend.o dwarf2dbg.o dw2gencfi.o ecoff.o ehopt.o expr.o flonum-copy.o flonum-konst.o flonum-mult.o frags.o hash.o input-file.o input-scrub.o listing.o literal.o macro.o messages.o output-file.o read.o remap.o sb.o stabs.o subsegs.o symbols.o write.o tc-i386.o obj-elf.o atof-ieee.o  ../opcodes/.libs/libopcodes.so -L/home/andreas/src/binutils/test/opcodes/../libiberty/pic ../bfd/.libs/libbfd.so -L/home/andreas/src/binutils/test/bfd/../libiberty/pic -liberty -lz ../libiberty/libiberty.a -ldl -Wl,-rpath -Wl,/usr/lib64
../opcodes/.libs/libopcodes.so: undefined reference to `_bfd_error_handler'

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510  2552 DF73 E780 A9DA AEC1
"And now for something completely different."