libbb/yescrypt: use common ACSII char-to-64 conversion code

function                                             old     new   delta
a2i64                                                  -      46     +46
yescrypt_r                                          1215    1235     +20
decode64_uint32                                      167     177     +10
atoi64                                                25       -     -25
ascii_to_bin                                          53       -     -53
static.atoi64_partial                                 77       -     -77
------------------------------------------------------------------------------
(add/remove: 1/3 grow/shrink: 2/0 up/down: 76/-155)           Total: -79 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/libbb.h b/include/libbb.h
index e88499a80..1c23d2f66 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -2190,6 +2190,7 @@ char *decode_base32(char *dst, const char **pp_src) FAST_FUNC;
 void read_base64(FILE *src_stream, FILE *dst_stream, int flags) FAST_FUNC;
 
 int FAST_FUNC i2a64(int i);
+int FAST_FUNC a2i64(char c);
 
 typedef struct md5_ctx_t {
         uint8_t wbuffer[64]; /* always correctly aligned for uint64_t */