Use libnghttp2.pc instead of nghttp2.pc

[dilyanpalauzov]

With 12.13.0 ./configure --help prints:

    --shared-nghttp2    link to a shared nghttp2 DLL instead of static linking
    --shared-nghttp2-includes=SHARED_NGHTTP2_INCLUDES
                        directory containing nghttp2 header files
    --shared-nghttp2-libname=SHARED_NGHTTP2_LIBNAME
                        alternative lib name to link to [default: nghttp2]
    --shared-nghttp2-libpath=SHARED_NGHTTP2_LIBPATH
                        a directory to search for the shared nghttp2 DLLs

nghttp2-1.39.2 installs libnghttp2.pc but not libnghttp2.pc . On my system pkg-config libnghttp2.pc --libs works and pkg-config nghttp2.pc --libs does not work.

./configure --shared-nghttp2 prints on my system:

Package nghttp2 was not found in the pkg-config search path.
Perhaps you should add the directory containing `nghttp2.pc'
to the PKG_CONFIG_PATH environment variable
No package 'nghttp2' found

Apparently, ./configure has to search for libnghttp2.pc, but looks for nghttp2.pc.

[bnoordhuis]

Can you check whether #30145 resolves the issue for you?

[dilyanpalauzov]

Now it prints

Package libhttp2 was not found in the pkg-config search path.
Perhaps you should add the directory containing `libhttp2.pc'
to the PKG_CONFIG_PATH environment variable
No package 'libhttp2' found

Apparently it searches for libhttp2.pc, but should look for libnghttp2.pc.

[bnoordhuis]

Yeah, somehow a typo snuck in. The last version of the PR should be good to go.

[dilyanpalauzov]

Now it works as expected.