Replace _Bool with bool in C interface headers for C++ compatibility

_Bool is a C11 keyword that is not recognized by C++ compilers,
causing build failures when PSBLAS headers are included from C++.
The headers already include <stdbool.h> (via psb_c_base.h) which
defines bool as a portable alias, so use bool instead of _Bool.

This fixes errors like:
  error: unknown type name '_Bool'
in psb_c_dsprn(), psb_c_ssprn(), psb_c_csprn(), psb_c_zsprn().

cbind/base/psb_c_cbase.h

@@ -62,7 +62,7 @@ psb_i_t		 psb_c_ccopy_mat(psb_c_cspmat *ah,psb_c_cspmat *bh,psb_c_descriptor *cd
 
 psb_i_t    psb_c_cspasb_opt(psb_c_cspmat *mh, psb_c_descriptor *cdh,  
  			const char *afmt, psb_i_t upd, psb_i_t dupl); 
-psb_i_t    psb_c_csprn(psb_c_cspmat *mh, psb_c_descriptor *cdh, _Bool clear);
+psb_i_t    psb_c_csprn(psb_c_cspmat *mh, psb_c_descriptor *cdh, bool clear);
 psb_i_t    psb_c_cmat_name_print(psb_c_cspmat *mh, char *name);
 psb_i_t	   psb_c_cvect_set_scal(psb_c_cvector *xh, psb_c_t val);
 psb_i_t	   psb_c_cvect_set_vect(psb_c_cvector *xh, psb_c_t *val, psb_i_t n);

cbind/base/psb_c_dbase.h

@@ -63,7 +63,7 @@ psb_i_t		 psb_c_dcopy_mat(psb_c_dspmat *ah,psb_c_dspmat *bh,psb_c_descriptor *cd
 
 psb_i_t    psb_c_dspasb_opt(psb_c_dspmat *mh, psb_c_descriptor *cdh,
  			const char *afmt, psb_i_t upd, psb_i_t dupl); 
-psb_i_t    psb_c_dsprn(psb_c_dspmat *mh, psb_c_descriptor *cdh, _Bool clear);
+psb_i_t    psb_c_dsprn(psb_c_dspmat *mh, psb_c_descriptor *cdh, bool clear);
 psb_i_t    psb_c_dmat_name_print(psb_c_dspmat *mh, char *name);
 psb_i_t    psb_c_dvect_set_scal(psb_c_dvector *xh, psb_d_t val);
 psb_i_t	   psb_c_dvect_set_vect(psb_c_dvector *xh, psb_d_t *val, psb_i_t n);

cbind/base/psb_c_sbase.h

@@ -63,7 +63,7 @@ psb_i_t		 psb_c_scopy_mat(psb_c_sspmat *ah,psb_c_sspmat *bh,psb_c_descriptor *cd
 	
  psb_i_t    psb_c_sspasb_opt(psb_c_sspmat *mh, psb_c_descriptor *cdh,
  			const char *afmt, psb_i_t upd, psb_i_t dupl); 
-psb_i_t    psb_c_ssprn(psb_c_sspmat *mh, psb_c_descriptor *cdh, _Bool clear);
+psb_i_t    psb_c_ssprn(psb_c_sspmat *mh, psb_c_descriptor *cdh, bool clear);
 psb_i_t    psb_c_smat_name_print(psb_c_sspmat *mh, char *name);
 psb_i_t	   psb_c_svect_set_scal(psb_c_svector *xh, psb_s_t val);
 psb_i_t	   psb_c_svect_set_vect(psb_c_svector *xh, psb_s_t *val, psb_i_t n);

cbind/base/psb_c_zbase.h

@@ -64,7 +64,7 @@ psb_i_t		 psb_c_zcopy_mat(psb_c_zspmat *ah,psb_c_zspmat *bh,psb_c_descriptor *cd
 
 psb_i_t    psb_c_zspasb_opt(psb_c_zspmat *mh, psb_c_descriptor *cdh,  
  			const char *afmt, psb_i_t upd, psb_i_t dupl); 
-psb_i_t    psb_c_zsprn(psb_c_zspmat *mh, psb_c_descriptor *cdh, _Bool clear);
+psb_i_t    psb_c_zsprn(psb_c_zspmat *mh, psb_c_descriptor *cdh, bool clear);
 psb_i_t    psb_c_zmat_name_print(psb_c_zspmat *mh, char *name);
 psb_i_t	   psb_c_zvect_set_scal(psb_c_zvector *xh, psb_z_t val);
 psb_i_t	   psb_c_zvect_set_vect(psb_c_zvector *xh, psb_z_t *val, psb_i_t n);