Improve documentation

Co-authored-by: Tom Cosgrove <81633263+tom-cosgrove-arm@users.noreply.github.com>
Co-authored-by: Werner Lewis <werner.wmlewis@gmail.com>
Co-authored-by: Minos Galanakis <minos.galanakis@arm.com>

Signed-off-by: Janos Follath <janos.follath@arm.com>

library/bignum_core.c

@@ -1,5 +1,5 @@
 /*
- *  Multi-precision integer library
+ *  Core bignum functions
  *
  *  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0

library/bignum_core.h

@@ -39,7 +39,7 @@
  */
 size_t mbedtls_mpi_core_clz( const mbedtls_mpi_uint a );
 
-/** Return the the minimum number of bits required to represent the value held
+/** Return the minimum number of bits required to represent the value held
  * in the MPI.
  *
  * \note This function returns 0 if all the limbs of \p A are 0.

library/bignum_mod.c

@@ -1,5 +1,5 @@
 /**
- *  Internal bignum functions
+ *  Modular bignum functions
  *
  *  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0

library/bignum_mod.h

@@ -101,7 +101,7 @@ void mbedtls_mpi_mod_residue_release( mbedtls_mpi_mod_residue *r );
 
 /** Initialize a modulus structure.
  *
- * \param[out] m     The address of a modulus.
+ * \param[out] m     The address of the modulus structure to initialize.
  */
 void mbedtls_mpi_mod_modulus_init( mbedtls_mpi_mod_modulus *m );
 
@@ -136,7 +136,7 @@ int mbedtls_mpi_mod_modulus_setup( mbedtls_mpi_mod_modulus *m,
  *          mbedtls_mpi_mod_modulus_setup() only removes the reference to it,
  *          making it safe to free or to use it again.
  *
- * \param[in,out] m     The address of a modulus.
+ * \param[in,out] m     The address of the modulus structure to free.
  */
 void mbedtls_mpi_mod_modulus_free( mbedtls_mpi_mod_modulus *m );
 

library/bignum_mod_raw.c

@@ -1,5 +1,5 @@
 /*
- *  Multi-precision integer library
+ *  Low-level modular bignum functions
  *
  *  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0

library/bignum_mod_raw.h

@@ -1,5 +1,5 @@
 /**
- *  Low level modular bignum functions
+ *  Low-level modular bignum functions
  *
  *  This interface only should be used by the higher level modular bignum
  *  module (bignum_mod.c) and the ECP module (ecp.c, ecp_curves.c). All other