Consistently use the name tinycrypt over uecc

We called in tinycrypt in the file names, but uecc in config.h, all.sh and
other places, which could be confusing. Just use tinycrypt everywhere because
that's the name of the project and repo where we took the files.

The changes were made using the following commands (with GNU sed and zsh):

sed -i 's/uecc/tinycrypt/g' **/*.[ch] tests/scripts/all.sh
sed -i 's/MBEDTLS_USE_UECC/MBEDTLS_USE_TINYCRYPT/g' **/*.[ch] tests/scripts/all.sh scripts/config.pl
diff --git a/tinycrypt/ecc_dsa.c b/tinycrypt/ecc_dsa.c
index ff8a78a..048fa61 100644
--- a/tinycrypt/ecc_dsa.c
+++ b/tinycrypt/ecc_dsa.c
@@ -53,7 +53,7 @@
  *  POSSIBILITY OF SUCH DAMAGE.
  */
 
-#if defined(MBEDTLS_USE_UECC)
+#if defined(MBEDTLS_USE_TINYCRYPT)
 #include <tinycrypt/ecc.h>
 #include <tinycrypt/ecc_dsa.h>
 
@@ -293,5 +293,5 @@
 	return (int)(uECC_vli_equal(rx, r, num_words) == 0);
 }
 #else
-typedef int mbedtls_dummy_uecc_def;
-#endif /* MBEDTLS_USE_UECC */
+typedef int mbedtls_dummy_tinycrypt_def;
+#endif /* MBEDTLS_USE_TINYCRYPT */