Remove unused macro

Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
diff --git a/library/ecp_curves.c b/library/ecp_curves.c
index aa2815a..a660f57 100644
--- a/library/ecp_curves.c
+++ b/library/ecp_curves.c
@@ -5526,7 +5526,6 @@
  * Write N as A0 + 2^224 A1, return A0 + R * A1.
  * Actually do two passes, since R is big.
  */
-#define P_KOBLITZ_MAX   (256 / 8 / sizeof(mbedtls_mpi_uint))      // Max limbs in P
 #define P_KOBLITZ_R     (8 / sizeof(mbedtls_mpi_uint))            // Limbs in R
 
 static inline int ecp_mod_koblitz(mbedtls_mpi_uint *X,