remove numerous unsigned int vs. int warnings

by setting all variables to type int.
Remove redundant function declarations by remmoving some includes
in span.c and vsrcdefs.h
In tmalloc convert int to size_t

src/include/ngspice/cktdefs.h

@@ -283,8 +283,8 @@ struct CKTcircuit {
 #endif
 /* gtri - evt - wbk - 5/20/91 - add event-driven and enhancements data */
 #ifdef RFSPICE
-    unsigned int  CKTactivePort;/* Identify active port during S-Param analysis*/
-    unsigned int  CKTportCount; /* Number of RF ports */
+    int  CKTactivePort;/* Identify active port during S-Param analysis*/
+    int  CKTportCount; /* Number of RF ports */
     int           CKTVSRCid;    /* Place holder for VSRC Devices id*/
     GENinstance** CKTrfPorts;   /* List of all RF ports (HB & SP) */
     CMat* CKTAmat;
@@ -295,7 +295,7 @@ struct CKTcircuit {
     // Data for RF Noise Calculations
     double* CKTportY;
     CMat* CKTNoiseCYmat;
-    unsigned int CKTnoiseSourceCount;
+    int CKTnoiseSourceCount;
     CMat* CKTadjointRHS;       // Matrix where Znj are stored. Znj = impedance from j-th noise source to n-th port
 #endif
 #ifdef WITH_PSS
@@ -460,9 +460,9 @@ extern int DCpss(CKTcircuit *, int);
 extern int SPan(CKTcircuit*, int);
 extern int SPaskQuest(CKTcircuit*, JOB*, int, IFvalue*);
 extern int SPsetParm(CKTcircuit*, JOB*, int, IFvalue*);
-extern int CKTspDump(CKTcircuit*, double, runDesc*, unsigned int);
+extern int CKTspDump(CKTcircuit*, double, runDesc*, int);
 extern int CKTspLoad(CKTcircuit*);
-extern unsigned int CKTmatrixIndex(CKTcircuit*, unsigned int, unsigned int);
+extern int CKTmatrixIndex(CKTcircuit*, int, int);
 extern int CKTspCalcPowerWave(CKTcircuit* ckt);
 extern int CKTspCalcSMatrix(CKTcircuit* ckt);
 #endif

src/include/ngspice/spardefs.h

@@ -25,8 +25,8 @@ typedef struct {
 
     unsigned SPdoNoise : 1; /* Flag to indicate if SP noise must be calculated*/
 
-    unsigned int SPnoiseInput;
-    unsigned int SPnoiseOutput;
+    int SPnoiseInput;
+    int SPnoiseOutput;
 } SPAN;
 
 /* available step types: XXX should be somewhere else */