linux: drop dead process field column DIRTY

The field for dirty pages in /proc/[pid]/statm is always 0 since Linux
2.6 (see man:proc(5)).

htop.1.in

@@ -392,9 +392,6 @@ except the process's executable instructions).
 .B M_LRS (LIB)
 The library size of the process.
 .TP
-.B M_DT (DIRTY)
-The size of the dirty pages of the process.
-.TP
 .B M_SWAP (SWAP)
 The size of the process's swapped pages.
 .TP

linux/LinuxProcess.c

@@ -56,7 +56,6 @@ const ProcessFieldData Process_fields[LAST_PROCESSFIELD] = {
    [M_TRS] = { .name = "M_TRS", .title = " CODE ", .description = "Size of the text segment of the process", .flags = 0, .defaultSortDesc = true, },
    [M_DRS] = { .name = "M_DRS", .title = " DATA ", .description = "Size of the data segment plus stack usage of the process", .flags = 0, .defaultSortDesc = true, },
    [M_LRS] = { .name = "M_LRS", .title = "  LIB ", .description = "The library size of the process (calculated from memory maps)", .flags = PROCESS_FLAG_LINUX_LRS_FIX, .defaultSortDesc = true, },
-   [M_DT] = { .name = "M_DT", .title = " DIRTY ", .description = "Size of the dirty pages of the process (unused since Linux 2.6; always 0)", .flags = 0, .defaultSortDesc = true, },
    [ST_UID] = { .name = "ST_UID", .title = "  UID ", .description = "User ID of the process owner", .flags = 0, },
    [PERCENT_CPU] = { .name = "PERCENT_CPU", .title = "CPU% ", .description = "Percentage of the CPU time the process used in the last sampling", .flags = 0, .defaultSortDesc = true, },
    [PERCENT_NORM_CPU] = { .name = "PERCENT_NORM_CPU", .title = "NCPU%", .description = "Normalized percentage of the CPU time the process used in the last sampling (normalized by cpu count)", .flags = 0, .defaultSortDesc = true, },
@@ -210,7 +209,6 @@ static void LinuxProcess_writeField(const Process* this, RichString* str, Proces
    case CMINFLT: Process_printCount(str, lp->cminflt, coloring); return;
    case CMAJFLT: Process_printCount(str, lp->cmajflt, coloring); return;
    case M_DRS: Process_printBytes(str, lp->m_drs * pageSize, coloring); return;
-   case M_DT: Process_printBytes(str, lp->m_dt * pageSize, coloring); return;
    case M_LRS:
       if (lp->m_lrs) {
          Process_printBytes(str, lp->m_lrs * pageSize, coloring);
@@ -330,8 +328,6 @@ static int LinuxProcess_compareByKey(const Process* v1, const Process* v2, Proce
    switch (key) {
    case M_DRS:
       return SPACESHIP_NUMBER(p1->m_drs, p2->m_drs);
-   case M_DT:
-      return SPACESHIP_NUMBER(p1->m_dt, p2->m_dt);
    case M_LRS:
       return SPACESHIP_NUMBER(p1->m_lrs, p2->m_lrs);
    case M_TRS:

linux/LinuxProcess.h

@@ -47,7 +47,6 @@ typedef struct LinuxProcess_ {
    long m_trs;
    long m_drs;
    long m_lrs;
-   long m_dt;
 
    /* Data read (in bytes) */
    unsigned long long io_rchar;

linux/LinuxProcessList.c

@@ -678,7 +678,7 @@ static bool LinuxProcessList_readStatmFile(LinuxProcess* process, openat_arg_t p
    if (!statmfile)
       return false;
 
-   long int dummy;
+   long int dummy, dummy2;
 
    int r = fscanf(statmfile, "%ld %ld %ld %ld %ld %ld %ld",
                   &process->super.m_virt,
@@ -687,7 +687,7 @@ static bool LinuxProcessList_readStatmFile(LinuxProcess* process, openat_arg_t p
                   &process->m_trs,
                   &dummy, /* unused since Linux 2.6; always 0 */
                   &process->m_drs,
-                  &process->m_dt);
+                  &dummy2); /* unused since Linux 2.6; always 0 */
    fclose(statmfile);
 
    if (r == 7) {

linux/ProcessField.h

@@ -19,7 +19,6 @@ in the source distribution for its full text.
    M_TRS = 42,                   \
    M_DRS = 43,                   \
    M_LRS = 44,                   \
-   M_DT = 45,                    \
    CTID = 100,                   \
    VPID = 101,                   \
    VXID = 102,                   \