REORG: buffer: rename buffer.c to dynbuf.c
The include part was renamed by commit 2741c8c but I somehow missed
the renaming of the C file, whose name didn't match the H file anymore.
diff --git a/Makefile b/Makefile
index d779009..04bf8a5 100644
--- a/Makefile
+++ b/Makefile
@@ -811,7 +811,7 @@
src/lb_map.o src/eb32sctree.o src/ebistree.o src/h1.o \
src/sha1.o src/http.o src/fd.o src/ev_select.o src/chunk.o \
src/hash.o src/hpack-dec.o src/freq_ctr.o src/http_acl.o \
- src/buffer.o src/uri_auth.o src/protocol.o src/auth.o \
+ src/dynbuf.o src/uri_auth.o src/protocol.o src/auth.o \
src/ebsttree.o src/pipe.o src/hpack-enc.o src/fcgi.o \
src/eb64tree.o src/dict.o src/shctx.o src/ebimtree.o \
src/eb32tree.o src/ebtree.o src/dgram.o \